Here's a Zeltex 101C octane test meter that I acquired on Racejunk.com for much less than the current new price of $11,000. It had been used for a few years by a dirt track owner for testing gas in some class of racers who were limited to using pump gas. He recently sold his race track in the Albany NY area, and had no more use for this equipment. But we surely can make good use of this for tuning trail machines on the dyno. And once again, who but me would be interested in buying a used octane tester? We often encounter what we think is substandard gas, and now we can be sure. The Zeltex octane tester uses near-infrared spectroscopy to measure both motor and research octane and prints out both along with R+M/2 and ethanol %.  These Zeltex testers are used by most states' Bureaus of Weights and Measures to test octane at gas stations. This one is calibrated to test unleaded gas with or without ethanol, and if I can obtain lab certified samples of commonly used race gas, it can be calibrated to do those, too.

Thursday, March 07, 2013

DynoTech : Reid Vapor Pressure Testing

Reid Vapor Pressure TESTING!

For race engine tuning, our biggest problem is stale race gas that racers buy unwittingly. Stale race gas can have excellent octane, but volatility can be poor due to the absence of important “light ends” of the fuel. Light ends are the first to escape into the atmosphere—creating that satisfying “whoosh” when sealed drums of race gas are first opened. But after gas is drawn and drum resealed, more light ends will escape into the air pocket above the fuel in the resealed drum. Then when the drum is opened again to draw more fuel, there is another, but less satisfying “whoosh” and more light ends escape into the atmosphere. By the time that large drum is consumed a few gallons at a time, no more “whoosh” is heard. Then the fuel is, for our purposes, “dead”. With the light ends that help initiate vaporization gone—escaped into the atmosphere—the fuel then needs excessive amounts of heat to get it to vaporize. Its volatility is now poor, and trouble is lurking for those who don’t understand what’s happening. I like to compare race gas’ “light ends” to the CO2 carbonation in 2 liter bottles of Coke. When first opened, the Coke is fizzy and good. But every time the plastic bottle is resealed then reopened later, more CO2 escapes into the atmosphere. And each time that happens, the fizz is diminished. After being opened and resealed a dozen times, that last swig of Coke you take from the bottom of the large bottle is awful—flat and fizzless, just like stale race gas.

What about those "sealed" 5 gallon “pails” of race gas? Are they filled and sealed at the refinery, or are they transfilled from open drums at a wholesaler’s facility and then “sealed”?? How long has that drum remained open? It pays to be leery!

Carl McQuillen Racing Engines in LeRoy, NY continues to manufacture and sell nitrogen pressurizing systems for drummed race gas. Those are a great tool for dispensing and storing race gas in 30-50 gallon drums, very much like draft beer systems do with CO2.

Poor volatility from escaped “light ends” can result in fuel failing to vaporize as it travels from the carbs/ throttle bodies into the intake ports/ crankcases (two-stroke)/ combustion chambers. We accurately measure our engines’ fuel flow as it travels from the fuel pumps into the engines, and we expect to see close to .60 lb/ hr of fuel for every HP the engine is generating. When practical, we measure airflow into the engines’ airboxes and .60 lb/hphr is typically 12/1 A/F ratio (12 pounds of air per pound of fuel). As a secondary source if information, we use an Innovate wide band A/F ratio meter that measures the exhaust gases coming out the pipes and gives us a chemical A/F reading that often is identical to the mechanical readings. As we approach maximum HP at 13/1 A/F, if octane is insufficient, we sometimes hear loud “clicks” of detonation on our copper tube sensor, and can abort testing before damage occurs. But stale gas measures pound for pound exactly like fresh gas, and what if only ¾ of the fuel is vaporizing in the combustion chamber? That means our indicated .60 lb/hphr is actually, net in the combustion chamber, .45 lb/hphr and that dandy 12/1 indicated A/F is, net, 16/1. In that situation, there might be zero clicks of deto, just wickedly net lean mixtures that cause pistons to grow quickly and stick in the cylinder bores! Our dyno flowmeters are indicating that all is perfect, but what it doesn’t tell us is the % of fuel vaporizing and burning in the combustion chamber vs. the % that finally manages to vaporize and burn in the hot pipes. If the gas is stale, all of our dyno meters can be telling us all is well, zero clicks of deto means octane is sufficient, and piston(s) can stick and spoil our tuning session. There’s nothing worse than a guy with a “stuck” engine having to have to pay for dyno time, take it home to fix it, then come back to retune with fresh gas and pay again.

My most recent obvious stale gas experience was my pal Gene Hurin (who’s been tuning here with his jet-changing wife Cathy for 25 years) coming here with a new HTG Polaris 1000 improver. He had bought 5 gallons of VP C16 gas from a local vendor, and Gene knew it came from an unsealed 55 gallon drum in the corner of the warehouse. Gene and I talked about the issues of stale gas before we began tweaking the Lectron carbs, but when we got down to ¾ turn on the power jets the engine seized with no warning at .60 BSFC and160 lb/hr of fuel flowing into the engine with 100 degree F coolant! Cringe. So Gene went home, fixed the engine, then came back again with Sunoco Maximal he bought from the infamous “Fat Nancy’s” in Pulaski NY who sells a zillion gallons of Sunoco race gas, and fresh is what Gene bought. This time with Gene’s orifice puckered severely, we leaned it down to 160 lb/hr, then continued leaning down all the way to 140 lb/hr and the engine was happy and powerful! It was much more pleasant charging Gene for the second tuning session.

How can we prevent future issues like this?

Kevin Cameron suggested that the important “light ends” of the fuel contribute substantially to Reid Vapor Pressure. Every name brand race gas has an RVP rating. That being the case, why not test dyno customers’ race gas for RVP before we wreck parts? What is RVP? How is an RVP test performed?

Thank you KC and Google! RVP is determined by precisely heating a quantity of gasoline to 100.0 degrees F + or - .2 degrees F. Then after agitating the 100.0F fuel, the pressure in a closed air chamber above the gasoline (4x the volume of the gasoline) is measured with an accurate bourdon tube test gauge and that is the exact RVP. The higher the RVP, the easier it is to vaporize, especially in cold winter air. Winter blended pump gas RVP is close to 15psi. Amond the lowest RVP even when fresh is C16 with less than 2psi! Trying to start a C16-fueled engine in February is impossible! Sunoco Maximal which has octane similar to C16 has 6psi RVP--a much better high octane fuel for cool engine performance in winter air.

If you watch dragracers "clean out" their engines on jackstands prior to the start of a race, you often hear them gurgle and pop for the first few quick blasts from clutch engagement to peak RPM. That gurgling you hear is lean misfire from cold low RVP gas going through cold carbs and into cold combustion chambers. Once the combustion chambers are heated, more of the lava-lamp-like globs of fuel will finally vaporize, and the engine will run cleanly. The higher the fuel's RVP, the better!

So let's just measure our fuel's RVP. Sounds simple enough, but when I found that the equipment needed to do this cost $7000—a $6000 precision water heater and a $1000 vessel for containing and measuring the fuel head pressure, I went to Ebay. There, I found an engine manufacturer’s surplus Koehler water bath used to precisely heat the fuel samples to 100.0F. Who in the world, but me, would want to buy a used RVP test bath? So it had languished on Ebay with zero bids since August, and I came along and “bought it now” for 20% of new cost. But it came with no fuel testing vessel—called a RVP “bomb” made of stainless steel, hydro-tested to 1000psi and a lab certified pressure gauge. I had to bite the bullet and buy a new fuel test “bomb” (yes, that’s what they call them!) from Koehler for $700, and a new $400 15psi .25% accuracy pressure gauge was Ebayed for $30. So now we can test for stale gas—hopefully before we wreck parts!

I hated high school chemistry. The only enjoyment I got from those awful lab sessions was making hydrogen bombs from dissociating hydrogen and oxygen from water then igniting those with a match.. Acetylene bombs were also great fun, especially when several of my equally deviant pals and I pooled our precisely rationed grams of calcium carbide to mix with water! But here I am, trying to figure out the Reid Vapor (Vapour) Pressure of racing gasoline! My annoyed chemistry teacher would be proud, if he were still alive.

An RVP test takes about an hour—about as much time as it takes to set up a sled or bare engine onto the dyno. So from here on, RVP testing can be done prior to race gas dyno testing/ tuning, so the one final mysterious variable might be eliminated.

Koehler RVP “Bomb”. The gasoline to be tested is poured into the shorter lower portion of the stainless steel cylinder, which unscrews from the hollow upped air chamber. After the lower chamber is filled with gasoline to be tested, it is attached to the upper chamber.

Here’s the RVP bomb sitting in the Koehler circulating water bath at 100.0F. It holds about 20 gallons of 100.0F water agitated by a propeller driven by the motor on the upper right.

The yellow temperature numbers are thermostat setting, and the red temperature numbers are the exact temperature of the water circulating around the “bomb”. Precision is required!

Friday, February 15, 2013

DynoTech : Boost, fuel flow, & ignition timing relationship

BOOST, TIMING, & FUEL

On the dyno, we often jockey ignition timing and boost pressure levels, to enable us achieve maximum reliable power on a given octane.  Do we go with more timing and lower boost, or less timing and more boost?  Less timing advance and higher boost mean higher exhaust temperature (and hotter pipes) helping drive the turbo’s exhaust turbine harder and more quickly and higher intake charge temperature (less dense and more prone to deto) especially on two-strokes that have some of the intake charge spend time inside the hotter exhaust header pipe on the bottom half of each piston stroke, before the returning sound wave shoves it back into the exhaust port. More timing and less boost can have the opposite effect along with the increase in transfer of combustion heat into the heads while the expanding burning mixture spending more time there driving the pistons down instead of burning in the pipe(s), making them hotter! But what about fuel flow? We can make max HP at about 13/1 A/F, but we get the greatest combustion chamber cooling effect (and least power output) at 10/1. What shall we do? Jockeying all three about, and watching for/ listening to detonation is what we must do while we observe torque and horsepower on the dyno (or observe clutch RPM during field testing—was that 50 more RPM, or 50 less RPM?).

Some years ago DynoTech was contracted to create an optimal pump gas tune (ignition timing curve, fuel flow, and boost level) for a turbocharged Buell motorcycle that was being considered for production (details of the turbo Buell “Diablo” were made public in Cycle World, May 2010, page 44). We built five Buell X1 engines/ bikes for H-D to test with custom dished low compression pistons with tight squish band clearance to obtain the combustion chamber turbulence necessary for rapid flame speed (which results in less ignition timing required to achieve best torque). We also designed and fitted each bike with efficient side-mounted intercoolers with plastic pro-stock style air scoops (there’s a photo of one of the turbo Buell X1 test bikes on our motorcycle dyno on this website when you click on “About DynoTech”). H-D had loaned us engineering software to enable us to tune the front and rear (hotter running) cylinders individually. Their target was 125+ rear wheel HP (about 50% increase over naturally aspirated X1s). After trying 100’s of combinations of boost/ ignition timing/ A/F ratio we wound up with front/ rear ignition timing nearly identical to the stock factory curves with boost pressure and fuel flow that made over 130 RWHP! Part of the H-D endurance testing that these bikes ultimately passed included filling the bikes’ fuel tanks with pump gas and [underpaid] test riders would run in high gear, WOT (at a high speed test track in Alabama) non stop until the tanks were empty—with no electronic deto protection! According to the CW article, the turbocharged Buell X1 test bikes exhibited greater reliability than the normally aspirated high compression X1s.

Tuesday, January 01, 2013

DynoTech : Winter testing schedule

12/14 Petschke Motorsports dyno testing the ETEC 800 with their new flowbench tested Y pipe results posted on this website members' pages

12/15 Keith Monroe, F7 w/ D&D trailport dissapointing performance last season was traced to a counterfeit BMP pipe modded stock pipe that Keith had bought on EBay. I was leery since the counterfeit pipe had poor welds, and my suspicions were confirmed when we installed the BMP modded stock pipe I have here for test purposes and picked up 13hp.

12/17 John Joyce,Wayne Yeardon, Rob Schooping testing Merc 440 freeair oval racer- Rob is back at his home shop now, back to his roots modifying/ porting engines. Since the Merc 440 piston port engines are similar to the powerful 650 Polaris triple engines Rob created back in the 1990s, these are a natural...

12/21 the worst day of testing ever--two sleds with freshly rebuilt engines, freshly installed back in the sleds with what appear to be air locked oil pumps...no premix in the gas, sled 1 (a big bore twin) locked up just before we began the test, at 12/1 A/F...a disappointing mystery but that can happen...then sled 2 made one pass loaded with fuel, then locked up like sled 1...autopsied that sled on the dyno, the bottom end was bone dry totally devoid of any sign of oil! Sled 1 was autopsied back home, bone dry like sled 2. Moral of this unhappy story is, whenever an engine is removed, then reinstalled, the first one or two tanks of gas should be premixed. They will be back, with slippery fuel in the tanks next time!

12/27-12/29 Pro race team testing, dynocams off 

1/2 Todd Dewind PCV tuning a 2012 ProR 800 w/ DynoPort pipe.

1/3 Josh Bender Boondocker tuning a trail mod Cat 800

1/6 Jesse Bradley, (Bradley Performance) PCV tuning a trail mod Cat 1200 (cancelled, waiting for parts)

1/7 Gus Bohne dyno tuning Art Bash's turbo Polaris 1000 triple, and another turbo MachZ twin (cancelled)

1/11 Cat F7 for Boondocker tuning

1/12 Dave Behuniak, Vmax 4 FPP lakeracer mod, turning new MSD

1/14 Gus Bohne dyno tuning Art Bash's turbo Polaris 1000 triple, and another turbo MachZ twin (results posted soon)

1/15 Wayne Tessier boondocker tuning early (moderate port timing) 800/901 Cat

1/16 Jake Lehnen making even more HP on his FPP SkiDoo RS600 hilldrag mod engine

1/17 Tony Koz tuning his XF800 single pipe improver Hilldrag sled

1/17 Mike Koz tuning his XF800 stocker Hilldrag sled

1/22  Jesse Bradley, (Bradley Performance) PCV tuning Jeff Sills' trail mod Cat 1200 (215hp 147 lb/ft on pump gas)

1/24 Crossfire 1000 boondocker tune

1/25 RJ Quell mystery tune

1/30 Pat Kitchen/ Cat 1500 triple w/ Boyd McGarry tig welding pipes

1/31 Kelly & Sandy O'Dell dyno tweaking SkiDoo 800 (one twin, one triple) promod hilldrag sleds

2/1 Adam Glick two big twin Cats for carb/ EFI tuning 

2/1 & 2/2 Kevin Freeman (Sled Shop SkiDoo in Presque Isle, ME) dyno verifying the tune on his FPP turbo Etec 800 (190+ click-free on ME 93 octane, will post the numbers)

2/5 Brian MacLaren PCV tuning a strangely deto-prone 2010 F8

2/8 Marty Rainville from Quebec, PCV tuning a stock F1000 for dragracing/ trail riding

2/11 Dynamo Jim testing stock turbo Cat w/  TD stage 5 w/ larger injectors cancelled, engine issues to address, will come another day

2/14 Jeremy Wilder, two SkiDoo 800s (one R, one HO) for hilldragging

2/19 Jake Lehnen- one more time with his FPP ported SkiDoo 600R hilldragger, this time with a late model "stuffed" crankcase--trying to match the Hentges Polaris 600 HP. Started months ago with 137 HP, last time here we were close to 160hp. Will post our step by step improvents, and how each improvement was accomplished on this website.

2/20 James Moore, tuning NA and N2O F7

2/21 Dan Brownell Crankshop 1500 triple

2/22 David Kirchhoff, FINALLY a Dragon 800 with FIX cylinders and pistons to create a proper PCV/ PC3 map! cancelled due to scuffed piston, will try again...

2/23 Brian MacFarlane F8 PCV tuning w/ BMP exhaust

3/2 Mark Fisher dyno tuning 800 triple and 600 twin improved stock engines

3/3 Jake Lehnen SkiDoo 600RS Full Power mod, one more time!

3/13 Renegade Rich Myers SkiDoo 800R mod hilldragger

3/15 Larry Audette ported Etec 800 looking for 170+ on pump gas

Friday, October 05, 2012

DynoTech : 2012 info & updates

GEORGE TAYLOR--74 year old George Taylor has died of heart failure. He had been a partner with DynoTech and American Snowmobiler Magazine for 22 years helping organize and orchestrate the annual stock sled Shootout in the Adirondack Mountains. George owned Van Aukens Inne near Old Forge, NY which was Shootout Headquarters for many years until it was sold. But in his retirement George stayed on with me to help organize the dealers, shootout facility, promotion etc each year. This year, Tom Smith is helping out in George's absence. Long time Shootout attendies will surely remember Tom, former owner of Smith Marine SkiDoo. About 20 years ago at the Shootout (then at the Old Barn Restaurant in Eagle Bay) Tom goofed on his "dealer prep" setup and both his SkiDoo stockers (a 580 and a 670) seized at 1000ft. Annoyed by a large group of jeering hecklers in the crowd, Tom retaliated by dropping his pants and flashing a horrible-looking moon (complete with awful Brahma bull-like swinging testicles) to the 1000 or so grossed-out but pleased spectators. To those of you who are coming to the Shootout this December, please do not annoy Tom!   

NEW NEIGHBORS--Jeff and Dave from JD Powersports have moved their facility from Rochester, NY to the west end of my commercial building in Batavia. They've set up a showroom/ office and their production welding equipment (for tig welding Arctic Cat stainless steel turbo pipes and mufflers etc) and their own SuperFlow 902 dyno right next door to me. Now my one neighbor who sometimes expresses his displeasure over the noise coming from my dyno room can enjoy the sound of howling engines in stereo! JD has just finshed dyno testing their "anti-lag" mode that they program into the stock Cat ECU, and plan to bring a machine fitted with that to our "Turbo Time" shootout in December. 

GOOD NEWS FOR ETEC OWNERS--next week DynoJet is sending me a preproduction Power Commander V for the SkiDoo ETEC system. Finally, we should be able to properly add the fuel necessary to support added airflow from Boyesen Rad Valves, Ypipes, pipes, porting, big bores etc. I need someone with a stock Etec 800 to come for a free tuning session, to assess how much fuel we can really add in high density (high baro, low temp refrigerated air) with the new PCV. NEWS FLASH 1/28/13 JUST GOT THE FIRST SHIPMENT OF PRODUCTION ETEC PCV's $499 PREMAPPED FOR YOUR COMBINATION, INCL FREE SHIPPING/ INS + 3 YRS FREE ADDED MEMBERSHIP TO DTR.

NEW SNOCROSS STOCKERS NEEDED! Free dyno tunes are offered for new Polaris, Arctic Cat, and SkiDoo 600 sleds. Also if there is a hotrodded Yamaha Nytro SnoX machine that could qualify for a free tune. We need to know how the new stock 600 class engines compare. Remember this year the mod 600cc SnoX sleds must retain stock engines (?!) except for pipes, compression, and ignition timing curves, and we need to see how the factories have reacted to this seemingly strange new rulebook. Call Jim 585-993-2777

Wednesday, September 19, 2012

DynoTech : Fall dyno schedule etc.

9/6 Charlie Bush, Polaris 700 triple HTG mod maxing out HP with fuel and timing tweaks

9/8 Adam Schmitt, Polaris 1000 triple HTG mod, maxing out HP with fuel and timing tweaks

9/9 Pete Nixon, AC800 twin, tuning for max winter HP in 28 degree F refrigerated air.

9/15 Nick Sampo, SkiDoo 800 triple grass drag sled, fuel and timing, pipe center section temp vs. max HP RPM.

9/22 Tim & Brian Tyler, Polaris PS800 twin

9/23 Dead One Dave, F7 stock hilldragger (new style Boondocker with % adjustments instead of milliseconds) winter air tune (28 degrees F)

9/23 Michael Koz, F6 stock hilldragger winter air tune (28F)

9/26 Wayne Yeardon XCR800 (shimmed w/ HTG pipes) asphalt drag ET sled

10/3-4 FPP Justin tuning a new Improved Stock SkiDoo 1000 triple

10/16-17-18 Etec800 stocker testing new production Boyesen Rad Valves and adding fuel with prototype Power Commander ..test results are posted

 10/19 FPP Justin back again with the Imp Stock SkiDoo 1000 triple

10/24 Jack Lloyd (Fourth Lake Performance) from Eagle Bay tuning Polaris 500 twin stock oval racer

10/27 Brent Brickler Boondocker tuning a Cat F1000 D&D ported and twin pipes, pump gas

10/28 Peter Nixon, private test session

11/1 Tripod Dan Cross testing & tuning John T Cowie's HTG1080 Polaris triple, now stroked to 1180 or something like that, just to run at Jiacobbe's Outlaw Shootout

11/2 Phil Perry, tuning a Polaris 700 twin hilldrag sled, full SLP mod engine with SLP twin pipes

11/2 Barry Taggart and Justin Fuller re-dyno testing a formerly fast Yam 700 drag engine but troublesome for the past two years--bad fuel flow once again rears its' ugly head. Solid mount engines must be balanced lke sewing machines if we expect high RVP race gas to stay liquid in the float bowls--this one was smooth and dandy first time at the dyno but something has changed the crank balance, and now the fuel turns to foam and engine runs lean...

11/7 Jack Lloyd with another Polaris 500 circle tracker owned by Dom Antonucci one of the Jack Lloyd built 500s won Eagle River last year..

 11/7 Jim Bristol boondocker tuning an Engine Tech F7/900 big bore...had trouble with Boodocker, left the sled on the dyno came back 11/8 with a good boondocker and got a good tune, albeit with a little less HP than hoped for--these big bore engine come in varying compression ratio and this one was surely on the low side but probably good for the notoriously poor gas we get on the trails in NY

11/10 Randy Calus, tuning an 09 Crossfire 800 with D&D shim kit

11/19 ProR 800 brought to the dyno by Casey Mulkins for Boyesen Rad Valve airflow and HP assessment, along with a coolant flow test comparing stock water pump impeller to a tall Boyesen billet aluminum impeller interesting results to be posted soon

11/21 Kyle Howard, SkiDoo 600 hilldrag sled, tuning for max power

11/24 Carl Theriault two Cat Turbos--one hot trail sled and one large turbo lakeracer cancelled due to coolant bubbles in the lakeracers--will be coming later

11/25 Jeff Sherlock tuning on a ProCross800 trail mod

11/26 Greg "Jaws"  Balchin coming back after his last dyno session here 22 years ago, demonstrating his new single pipe on a stock ProCross 800

11/30 Heath Link dialing in a little N2O on his polaris 800 triple, along with his pal Randy who'll be dialing in a LOT of N2O on his 1200 twin last time Heath was here with his Polaris 1000 triple trail sled, he was delighted with the work Californian Nate McCoy (racemotors@juno.com) did for him, including a custom timing map for his Polaris ECU that complimented the Jaws triple quiet pipes creating a flat easy to clutch HP curve...

12/3 HELL WEEK..Tom Smith is bringing a huge trailer-full of stockers to dyno certify for the AmSnow DTR Adirondack Shootout. Tom is going gung-ho to keep the stockers stock, maintaining possession of all the stock sleds from setup at the dealers until they're unloaded at White Otter Fish and Game club in Woodgate,NY on Friday 12/7...

Thursday, September 06, 2012

DynoTech : AmSnow/DTR Shootout at Woodgate NY

TURBO TIME AT THE ADIRONDACK SHOOTOUT

This is an invitation for all Arctic Cat Turbo commercial tuners/ modifiers/ manufacturers of mufflers, intercoolers, etc to bring a true trailable turbo Cat to this year’s AmSnow/DynoTech Research Shootout at Woodgate. AmSnow editors Mark Boncher and Mark Savage are working with us to make this possibly the most entertaining Shootout in 22 years. Or is it 23 years? I’ve lost track!

The plan is to offer FREE ENTRY to any company that wants to show off the performance capability of their Cat Turbo tuning and parts. For the “TURBO TIME SHOOTOUT”, the participating company is only required to be a minor advertiser in AmSnow (such as a website banner advertiser) instead of the display ad requirement! Thanks to AmSnow for cutting some slack this year to make this a no-brainer for any company that deals with Cat turbo stuff!

The concept is to have equal weight stock chassis sleds with STOCK TURBO, stock OEM track with trail carbide studs, some acceptable minimum weight, a real muffler of some sort, and anything else should be OK. No other power adders, lowered 2” maximum from stock at each end.  Anything else?

We’re looking for feedback from interested aftermarket companies. So far I’ve communicated with D&D, JD Powersports, and Arctic Adventures (new U.S. distributors for Canada’s Turbo Dynamics) and all are committing to participate.

There will be LARGE separate trophies for FASTEST M.P.H. and for QUICKEST E.T. in 660 FT.

Also, any aftermarket company wanting to showcase higher power (ie: large turbo) sleds can run them in the lakeracer class, where anything goes.  And, we’ll still be running true pump gas trail mod sleds as we’ve done for many years. Those sleds cost $500 each to demonstrate, with awards for many "classes" given out at the Shootout banquet.

Interested companies can call me at 585-993-2777 or email me at info@dynotechresearch.com

On a sad note, our Shootout partner (since Shootout #1) and good pal George Taylor died of heart failure last week. George's long time friend Tom Smith is going to handle George's Shootout work this year.  

Monday, July 30, 2012

DynoTech : spring/ summer dyno schedule

4/2 Pat Kitchen, Joe DiSpirito Cat 1500 triple asphalt sled

4/6 Jim Sigg 103ci H-D PCV tune (CycleDyn)

4/7 Don Puleo 107ci H-D PCV tune (CycleDyn)

4/12 Randy Crouse, Cat 1200 twin, tuning N2O

4/13 Heath Lynk Pol 1080 triple trail sled

4/13 Harry Jones Honda CRF450 flattrack bike (CycleDyn)

4/22 Ron Jewell Kenny Coolbeth KX450 (CycleDyn)

4/25-5/6 Todd Hogan testing Boyesen Rad Valves on Etec 800, compare early ecu flash to 2013 flash-- results posted

5/6 Troy Butts Yam YZ450 (CycleDyn)

5/6 Mike Luczak Honda CRF450 flattracker (CycleDyn)

5/11 Ron Jewell/ Kenny Coolbeth Kaw KX450 one more time (CycleDyn)

5/12 Cody Fowler Hayabusa PCV tune (CycleDyn)

5/20 Dave Wells Honda CRF450 flattracker (CycleDyn)

5/23 Don Ohlson Hayabusa PCV tune (CycleDyn) we tuned this bike a year ago, ran perfectly until this spring then began losing power and finally broke a connecting rod. New engine was installed and it ran perfectly while cruising but at high revs WOT would lose HP. So back to the dyno A/F was perfect until WOT high RPM then it would go lean (instead of the proper 12/1 it would show 16 or 17/1!). PCV adjustment made no difference. So we checked fuel pressure and as expected the fuel pressure dropped as revs climbed meaning plugged fuel filter/ defective fuel pump. Don tried a new filter and fuel pressure still dropped at high revs, then he sprung for a new in-tank fuel pump and all is perfect now. So that tired $350 fuel pump cost him a $5000 engine repair. Moral of this story--if your EFI engine begins to lose power at high revs CHECK THE FUEL PRESSURE.

5/24 Mike Zacher CRF450 and CRF100 Flattrackers (CycleDyn)

5/24 Brian Neuman CRF450 Flattracker (CycleDyn)

5/24 Wade Blood Kawasaki Vulcan PCV tune (CycleDyn)

5/27 Neil Jacobs tuning 107 cubic inch 280hp Kaw Pro Stock dragbike on the 902 shaft dyno

5/28 Frank Burns H-D VRod big bore PCV tune (CycleDyn)

6/1 Dave Wells tuning CRF450 with Ron Jewell mod (CycleDyn)

6/9 Al Rowcliff CRF450 with Ron Jewell head (CycleDyn)

6/9 Frankie Amalfi and Yammigod Tony Yam SRX700 asphalt racer

6/13 Bill Woodley TC88 PCIII tune (CycleDyn)

6/23 AJ Frank using 902 shaft dyno to tune his trail mod Banshee 350 quad

6/24 Aaron Mucher Yamaha FZ1 PCV tune (CycleDyn)

6/25 Jerry Jankowski Honda Blackbird Turbo carb tune (CycleDyn)

7/1 Brad Crocker setting up his Bender Pol 600 mod engine for H2Ocross racing

7/21 Keith Crowell Yamaha R6S streetbike PCV tune (CycleDyn) 

7/28 Jake Lehnen searching for power with his SkiDoo RS600 hilldrag sled

8/2 Pat Kitchen again with 1500 triple Joe D engine

8/3-8/30 intermittent private testing cameras off

8/31 Tim Tyler Polaris 800 twin drag engine

Tuesday, May 29, 2012

DynoTech : Kevin Cameron-the history of combustion chamber design, and applying that info to help engine performance

Wednesday, February 15, 2012

DynoTech : Bad octane, Gus Bohne 1080 turbo, etc

BAD OCTANE

Octane cheating either intentional or otherwise seems worse this season than ever before! Why do we suspect that? We can hear pump gas detonation on the dyno more this year than in years past! It appears that more than ever before, people come here to tune their trail sleds with their own “fresh high test” and discover here that it’s really “low test”. Often, when we experience unusual detonation we can buy 93 octane from another gas station, and the knock goes away.  I often talk about the NYS Bureau of Weights and Measures who reports that roughly 10% of gasoline they test in this state is substandard. Dateline NBC took it upon themselves to test octane at California Exxon stations, and out of 85 samples of high test gas one in eight was substandard—the worst of which tested at 75 octane! Car and Driver wrote that the state of Michigan’s Bureau of Weights and Measures found that out of 2,816 samples of high octane pump gas, 217 were low octane. Is your state or province any different? 

How can we hear detonation occurring on the dyno? Sean Ray learned about listening to engine knock several years ago at Delphi where he is employed as a calibration engineer. Hyundai engineers came from Korea to Sean’s Delphi dyno cel with a roll of ¼” ID copper tubing that they attached to the engine Sean was calibrating for them. They drilled a hole in the control room wall, bolted the copper tube to the Hyundai engine and inserted the other end into the control room, just dangling in the air. Delphi engineers could now hear every click of detonation—which makes a loud snapping noise that emanates from the copper tube in the control room—sometimes even before the engines knock sensors could notice it! Sean brought the copper-tube deto sensor concept from his Delphi engine dyno cel to DTR several years ago. It’s an incredible tuning aid, and has saved many hundreds of pistons to date! We now listen for detonation here and usually can abort any test before engine damage occurs. Three or four audible clicks and we quit the test. On two-strokes we will never hear more than about twelve clicks of detonation—the engine will have seized by then!  Last season Sean and Tim Bender ran over 700 max power dyno tests on one mule 600 race engine for Hentges Racing, and lost zero pistons because Sean could hear clicks and abort. During similar max power testing in years prior to the copper tube, Tim used to bring a box of pistons and a jug of muriatic acid to clean the bores after seizing. Back then it was more wrenching and less testing. But today it’s much more efficient thanks to Sean’s Korean engineer pals!

Four-strokes can be more forgiving—each detonating compression stroke is followed by a piston-cooling intake stroke. This means that a few more intermittent clicks of deto can be heard and tolerated by the engine before really bad things happen. Four-stroke piston seizures from deto are rare. Instead, when continual deto makes spark plug ground straps red hot, preignition can occur which can create the worst damage! Then, peak pressure will climb to the moon, which can crack ring lands, stretch the head bolts/ studs and either blow the headgasket(s) or just lift the heads enough to allow combustion pressure into the coolant passages, spewing coolant out the reservoir overflow. Too often people try to rectify detonation problems not by increasing octane or more conservative tuning, but instead by using stronger head bolts/ studs, O-ringing combustion chambers, copper headgaskets, etc. Then, instead of blowing headgaskets we might see studs being pulled out of the crankcase threads, conrods bend or break and cylinder and head gasket sealing surfaces fried into junk as though attacked by a plasma torch!  Tune those high boost engines! Don’t scrimp on octane!

With proper tuning for the available octane, stock fasteners and headgaskets will survive incredible power increases! Justin Fuller of Full Power Performance prefers stock head fasteners in his 200-400+ HP turbocharged Yamaha four strokes—noting that stock fasteners are designed to stretch and continue clamping properly as the aluminum heads grow with normal heat expansion. Heavier larger diameter high tensile strength fasteners may not stretch enough as the aluminum heads expand and can instead create severe cylinder head distortion that can cause compression/ coolant leaks even where no severe detonation occurs.

So, back to the issue at hand—what do we do about this awful situation regarding cheating on octane? To be safe and conservative, ALL HOTROD TRAIL SLEDS SHOULD BE TUNED TO BE DETONATION-FREE ON 87 OCTANE! A conservative tune for 87 octane might result in only 3-4% reduction in peak HP so it’s not a great penalty to pay. Then, leaner jetting or a second more powerful Boondocker or PCV map can be used for lake racing etc when a few gallons of race gas/ av gas can be added to the tank for safety.

It’s quite possible that when we tested Gary Berwind’s Z1 turbo with the Turbo Dynamics’ 4 stage tune, he may have had less than 93 octane in his tank even though he paid for 93 octane that day. Severe detonation made it impossible to run the high power settings without water/ methanol and lots of it!  But now, after this dyno tuning session Gary can probably run his sled anywhere with any octane gas. He just needs to have his water/ methanol reservoir topped off, typically with windshield washer fluid. My opinion is that anyone with an overboosted Z1/ F1100T should run race gas, and/ or invest in a water/ methanol injection system. So WHEN (not IF) you buy 85-87 octane even though the pump sign indicates 91-93 octane you won’t need to depend upon factory knock protection to save your engine. And remember, the factory Z1/ F1100T ECU will not look for deto above 8300 RPM!

My own experience with boost and water/ methanol is with the used Whipple supercharger I bought from my pal Rusty in Rapid City SD for my 2002 Chevy Avalanche 5.3 liter V8. Based upon Sean Ray’s calibration work at Delphi we understand that the 5.3 is tuned to the edge of deto NA. So adding boost, especially with no intercooler, is almost guaranteed to create knock. With 6-7 psi boost, my Whipplecharged 5.3 would just pull lots of timing in reaction to light deto even with Sean’s reprogrammed EFI Live tune that gave us 11.0/1 A/F ratio on boost. The knock-induced retarded timing severely limited the power increase.  But by adding a water/ methanol injection system the compressed charge temp is drastically cooled to about ambient temperature, and I can run knock-free now with 6psi boost on 87 octane gas. The water/ methanol condenses the compressed intake air thus dropping observed boost pressure a bit with the fixed speed supercharger.

ANOTHER EXCELLENT AFTERMARKET ARCTIC CAT 1000 Y-PIPE

Ted from Terra Alps Racing in British Columbia, Canada (www.terraaplpsracing.com)  sent us a stamped Y pipe he makes and sells for Cat 1000 twins. Local Cat wrench Don Zuzze brought this 2007 F1000 bone stocker for a PCV tune, and we tested the Terra Alps Y-pipe compared to the stock Y-pipe as shown here. Adding 5% fuel at 100 and 80% throttle positions with a PCV, the A/F ratio was held constant. As shown in the following graph, HP is improved from midrange to top end. And note the precision of the control of fuel flow by the Power Commander.

SHRINK WRAPPED vs BATHTUB HEADS and BLOCKS

A few weeks ago I got my first close look at the Ford FR9 NASCAR race engine designed by RoushYates on an episode of “How It’s Made”. In this program, we can see how both the heads and block have that “shrinkwrapped” appearance—the external surfaces closely match the perceived shapes on the internal structures of the heads and block!

Here’s a good side view photo of the engine:

http://www.google.com/imgres?imgurl=http://image.hotrod.com/f/30726978%2Bw750%2Bst0/hrdp_0911_01_z%2BNASCAR_race_engines%2B.jpg&imgrefurl=http://www.toonutsracing.com/smf/index.php%3Ftopic%3D928.0&h=480&w=640&sz=50&tbnid=45Tpd7WlDiKwZM:&tbnh=101&tbnw=134&zoom=1&docid=QxBrKk8UckgUZM&sa=X&ei=aHw5T5KzOZK_0QGd76iwAg&ved=0CDoQ9QEwAg&dur=2099

HTG POLARIS 1080 TRIPLE w/ GUS BOHNE TURBO SYSTEM

Gus has the carb issues on Art Bass’ turbo 1080 resolved, and now we were able to tune it on the dyno. But it didn’t take long to see that the triple pipes on this sled were too short, causing HP to climb with revs until I let off the throttle at 9800! Note that torque has not yet peaked at 9800. But if I stayed into the throttle the torque and HP peaks would surely have gone beyond 10,000, totally unnecessary with a big boosted engine like his. So Gus is going to lengthen the pipes enough to bring peak power down into the 8500-9000 RPM range. Then he and Art can come back to DTR and turn up the boost!

Sunday, December 04, 2011

DynoTech : Winter dyno schedule

11/4 Dead one Dave tuning his new stock engine 2012 Procross 800 for max power for hilldrags.

11/7 WakPak Joe tuning a 1000 twin for hilldrags.

11/11 Sean Weir with a SnowCross 600 mod SkiDoo. Also Tom Bachly with a new 2012 bone stock SkiDoo 600RS, tuned for max HP dyno test and tuning info posted on members' section now.

11/12 Bill Gregory, SkiDoo 800 triple mod, dialed in a dandy timing curve on his MSD.

11/19 Don Zuzze PCV tuning two seemingly identical F6's (required totally different maps) and one F1000.

11/20 Rob Lathrop fine tuning for max HP on a full mod SkiDoo Trigstad 600 twin. Also Dave Lathrop with an improved stock SkiDoo 800 twin also getting ready for hilldrags. our new data acquisition system gives us a "Density Altitude" reading while we test. DA is a combination of baro pressure, temperature, and humidity (water grains per pound of air). With max power carb dyno jetting created here at a given DA, we can then use a Kestrel 4500 Racing Weather Station wherever you're racing to get accurate DA. Then using just the altitude half of a Mikuni Pocket Tune sliderule, perfect jetting can be maintained. Pro racers tune at DTR then with this system perfect max HP jetting can be maintained froom sea level subzero to mountain racing out west.

11/21 D&D Dale & Glenn tuning for high safe pump gas HP with production F1100T. Muffler testing, HiJacker testing, all with stock turbo outlet pipe.

11/26 anonymous tuner, top secret today.

11/27 Mark Fisher getting ready to hilldrag with a Sherlock Crossfire 800/ Jaws race pipes.

11/28 TurboDynamics Ben with his production F1100T, testing his various ECU tunes all with high flow turbine outlet pipe and stainless steel fairly quiet muffler. to be posted soon

11/29 greedy Bill Swoyer looking for even more HP out of his CrankShop 1500 hilldragsled. Larry-this sled needs to run in the AmSnow Adirondack Shootout on 12/9! We have an all-motor class in the Lakeracer division!

11/29 WakPak Joe with his 1000 twin again, looking for more HP.

11/30 Vintage oval racers Brandon Hadley and Al Young tuning two race sleds--a SkiDoo 340RV and a Polaris TX440 for Eagle River.

12/1 Mad Canadian Gerry Prosser (Bender Canada) PCV tuning an EXUP Apex with Yamacharger, and trying out stock vs MBRP vs Bender vs D&D mufflers. this data may be posted on members' pages in later December. 

12/1 D&D Dale testing stock 2012 Apex then upgrading HP with PCV, D&D Stainless muffler, and high flow airbox cover and high RPM carb inlet boots. will post this after the 12/9 Adirondack Shootout  

12/1 PM Dale demonstrating big HP on their trail ported/ single pipe 2012 ProCross 800. will post this after the 12/9 Adirondack Shootout

12/4 Gary Foster tuning his 07 crossfire 800 with D&D shim kit and porting by Dale Fredericks. the dyno cold intake air refrigeration was necessary to get accurate winter tune today. outside air was 55 deg F, so intake air was chilled to 25 degrees.

12/4 through 12/7 certification dyno testing all of the Adirondack Shootout stockers--new Polaris dealer this year Bill Lutz of Fun Unlimited in Gouvernor NY. Also Tuesday we're doing all the Cats, plus hilldrag sleds the Michael Koz and Jeff Cerio need to sneak in for a quick tune.

12/11 Gary Berwind testing his Z1 w/ large intercooler, water methanol inj, Turbo Dynamics 4 stage tune on real pump gas. results posted on members' pages

12/13 Michael Kozlowski getting ready for hilldrag season

12/16 Allen Young, tuning Polaris TX440 freeair vintage oval racer

12/18 FPP Justin testing a Yamaha RX1 with 44 Megatron carbs replacing the stock CV carbs. significant gains in airflow and HP

12/19 Tim Huber getting it spot-on with his Crossfire 1200, Boondocker N2O

12/19 Jake Lehnen using his gift certificate to test and tune his Crankshop 600 hilldrag mod sled

12/22 Dave Patrick dials in his BMP piped Crossfire 1000--one tune for Oneida lakeracing at .55 and another tune for trail riding with Tug Hill mystery gas at .60

12/26 Zach Brown getting the most tunable HP out of his Merc 440 SnoTwister vintage racer.

12/26 Steve Stasko with another vintage racer--Polaris TX440

12/27 Gus Bohne/ Steve Duetti/ DNE gonzo turbo tuning session with mega-boosted HTG 1080 triple, MachZ1000 twin, DNE1700 quad-- HP records are smashed today, then posted on the members' section of this website

12/31 AMA racer Kenny Coolbeth's 2012 Kaw 450 flatrack race bike, Ron Jewel (RLJ Racing) modified engine tuning for every tenth of a HP on our CycleDyn. Also Ron's brother Randy tuning his HO800 for max power on pump gas. "who'd a thunk" we would need to refrigerate outside air to properly tune a sled on 12/31! But decent air for tuning a race bike!

 1/2 Trevor Chadwick's SnoPro600/ SS900 big bore doesn't anyone make a 12 degree offset timing key? Carl McQuillen Race engines, LeRoy NY EDM's offset keyways in Cat flywheels, Trevor needed lots more timing to make max HP on the big bore--first 10 degree keyway they've done.

1/3 Jason Yandricha--SkiDoo 800 triple shoehorned into a rev 440 chassis with a dandy motor mount kit from Bondi. hit the rev limiter way before the HP peak was reached, needs to get ECU reprogrammed to take care of that.

1/3 Jeremy Rataczyk--another F9ss engine--this one in a 440 SnoPro chassis, complete with EFI.

1/5 JD Powersports, getting independent test results of their new F1100T with their 4 stage ECU tune. results will be posted 1/26

1/6 Justin Hulsizer PCV tuning his F6/ 800 Jeff Stinson Big Bore with D&D Monster Twin pipes.

1/11 JJ Elmer getting his stock Mach Z twin w/ CS quiet twin pipes ready for Onieda Lake (if it ever freezes!). needed to refrigerate and dry the dyno intake air on January 11 to get a good 20 degree F boondocker tune!

1/15 Jeff Sills 2009 Crossfire 1000 w/ D&D Ypipe and pipe, creating one good trail map and one lakerace map. finally--we have cold outside air for tuning.

1/18 Andy Stiles testing pipes, and fine tuning his Polaris 600 ex-Hentges Racing hilldrag mod

1/19 George Brown and Wayne Yeardon, back for even more HP with Zach's 440 SnoTwister

1/24 Jason Owens, trying for more HP with HJ Schroeder's Cat PS1000 twin.

1/25 518er Todd Hogan with some sort of HillDrag SkiDoo

1/27 Craig Gabel Cat 500/ 720 Big Bore

2/1 or therabouts turbo maven Gus Bohne with the boosted HTG 1080 triple, looking for lots of HP. 

2/4 Hank Yeomans, F7 HillDragger

2/14 Jake Lehnen SkiDoo 600rs improved stock Hilldrag sled

2/19 Dave Behuniak and Al Miller tuning Yamaha lakeracers with Justin Fuller

3/1 Jake Lehnen one more time

3/2 Todd Hogan SkiDoo 800 hilldrag sled

3/8 Matt Boardway Polaris ProR 800 hilldrag stocker

3/10 Tim Wood AC F7 hilldrag stocker

3/17 Heath Lynk HTG 1000 asphalt racer

3/17 Randy Crounse AC F12 with n2o

3/21 Jim Stanley/ Glenn Hall AC Z1 D&D big turbo lakeracer

3/24 Justin Fuller Yam SRX700 prostocker

3/30 Paul Cross Wildcat 700 mod

Saturday, November 12, 2011

DynoTech : SuperFlow 902 dyno terminology explained

Dyno Terminology—Fresh and Refresh

The new SuperFlow 902 software has some subtle differences in channel headings in our test data compared to our original 25 year old  SuperFlow 901 software. For long term DTR members I need to clarify the difference, and for new DTR members I need to explain the channel information in our dyno printouts, and what each channel means to us.

EngSpd RPM self-explanatory—this is RPM, and on engines with digital tachs, the readings have proven to be identical from dyno to sled. But analog sled tachometers are another story—vast differences can be seen from digital dyno RPM to analog sled tachometer readings. So it pays to have analog sled tachometers calibrated electronically (Aaen does this for a small fee) or with a digital tach like those sold by Stihl (less than $100) for tuning chainsaws. Those are perfectly accurate. But keep in mind that the peak HP RPM on our dyno tests is with pipe(s) extremely hot. And since the speed of sound increases with temperature, the HP peak in the field may be at lower RPM (trail riders on-off-on throttle) or at higher RPM (lake runners or mountain climbers who might spend minutes at WOT). Sled dragracers used to think that they achieved best acceleration by clutching to the “peak torque RPM” which often occurs 2-400 rpm lower than dyno test HP peak. But now we know that we clutch to a shifting HP peak—cool pipes on takeoff will make peak HP several hundred RPM lower than hot dyno test pipes, and finding that constantly changing peak HP RPM is critical in creating best acceleration.

STPPwr CHp horsepower, corrected to 60 degrees sea level baro 29.92 in hg.
This is derived by taking RPM x torque lb/ft divided by 5252. Complicated initially but it takes into consideration the twisting force and how quickly it can be done (RPM). HP is what we need to create acceleration and maintain top speed. Read on:

STPTrq Clb-ft this is the twisting force, or torque that the crankshaft is exerting at any given RPM, corrected to 60 degrees sea level barometer 29.92 in hg. But by itself, torque does no work—it takes speed—lots of speed—to do meaningful “work” (HP). To emphasize that, I sometimes talk about me (200 lb Jim) riding my Schwinn bicycle with 12” long pedal cranks. With my 300 lb girlfriend riding on my shoulders (facing forward of course), by grunting and lifting my butt off the bike seat I can make 500 lb/ft of torque at the pedal crank! That kind of torque should create wicked acceleration, shouldn’t it? But my spindly legs can only muster 3 RPM! So based upon the math RPM x torque lb/ft/ 5252 = HP that means that I can make about ¼ HP. Not bad for a 62 year old. But if I were instead twisting the throttle on a Honda 90cc scooter with 8 lb/ft at 5000 rpm I would be making 7.5HP—accelerating much harder—even with my 300 lb honey riding with me! No contest. It takes HP to create acceleration. We need a combo of torque and lots revs to do work—to make HP. 

FuelAB- fuel flow into the engine in pounds per hour. This is a combination of the two dyno fuel flowmeters (flowmeter A and flowmeter B), measuring fuel flow from the sleds’ EFI pump to the rail, or from the mechanical pump to the carbs. Flowmeters can be used individually to measure N2O flow separately from carbs/ EFI. But combining the two flow readings is necessary for computing BSFC.

FulA_B- fuel flow from EFI pump to rail (A) minus fuel flow from bypass regulator back to the tank (B). Can’t use a – so we must use a _ instead. Polaris uses this type of system.

BSFCAB and BSFA_B- pounds of fuel per HP per hour. 25 years ago when I bought this dyno system there was no manual to explain the significance of this number. Early adventuresome guinea pigs (including all of the current eastern US aftermarket sled modifiers) and I proceeded to just tune engines blindly to max HP and beyond until engines seized. But after our 100^th piston or so, we realized that there was a pattern to this destruction if we went too far beyond max HP.  Fuel flow is meaningful information and we finally understood that our race engines would make best power at @.55 lb/hphr and pump gas engines needed @.70 lb/hphr to be reliable. Don’t go lower than that! But today, with modern race engine configuration two stroke race engines can make best power closer to .50 lb/hphr and new stock engines can be completely reliable at .60 lb/hphr and even lower! SkiDoo ETEC EFI systems allow way less short-circuiting, and a greater percentage of fuel flow contributes to HP, and not blowing out the exhaust thus reducing BSFC to bizarrely low numbers.  New cooling system designs like those used by Arctic Cat employ modern “reverse” cooling systems like all modern automotive race engines, deliver the lowest temp coolant to the combustion chambers where it’s needed most allowing way more deto-free power! High volume “bathtub” coolant passages are passé, and smaller volume but higher velocity “shrinkwrapped” head coolant passages scour heat from combustion chambers way more efficiently! They use high velocity, turbulent coolant flow to maximize heat transfer from hot engine parts to cold heat exchangers. “Low and slow” is for smoking barbecue meat, and for smoking pistons!

Air_1s scfm- This is the airflow through the engine in Standard Cubic Ft per Minute. The dyno flowmeter is affixed to the airbox, or inserted in the insulated duct from the DTR refrigerated air system to the sleds’ air intake.

AFRAB and AFRA_B ratio- this is the mathematical ratio of air pounds per hour/ fuel based upon the weight of the air (converted from CFM based upon air density) to pounds of fuel per hour. 10/1 is rich (richer than 10/1 can result in misfire), and 17/1 is lean (leaner than 17/1 can result in misfire).

LamAF1- the SF902 uses an Innovate wide band A/F ratio meter to measure exhaust gas, and give us A/F ratio readings. The O2 sensor can be plumbed into the exhaust via a bung welded into the pipe, or with a dyno probe—with a long ¼ ID steel tube inserted colonoscopy-like into the stinger/ muffler. This reading can show leaner than the mechanical reading if oxygenated fuel is used.

LM1air- if there is no airbox and no possibility of accurate airflow readings, then approximate airflow SCFM can be determined by comparing mechanical fuel flow and the wideband A/F ratio. The math is done by the 902 computer and SCFM is shown.

ExhPrs psig- this is the average gauge pressure inside the tuned pipe(s) measured with a combination pressure transducer/ open element temperature probe in the fat part of a pipe center section. To generalize, 4.0 psi seems to be optimal in creating max HP in two stroke engines. If backpressure is lower, then power might be sacrificed. But then there is less possibility of detonation-producing active radicals being packed back into the combustion chamber by the pipe(s) return sound wave(s).

Exh_1 deg F- this measurement tells us that a pipe is at optimal temperature for best HP. Also it’s critical in telling us where peak HP occurs. The most savvy clutch tuners/ dataloggers can use this particular dyno test data to ensure that their engines run at max HP RPM from clutch engagement to the end of the track, or to the first turn.

Tuesday, September 13, 2011

DynoTech : Fall testing schedule

9/8 unnamed Cat F6 stock dragracer, PCV tuning for max HP

9/11 Frankie Amalphie Yam SX700 triple asphalt racer, PSI Modblasters

9/11 New Superflow coolant flowmeter arrived today!

9/12 Kevin and Nick Albright nostalgia sled tuning- two Merc 340 (one snowttwister, one trailtwister) needed the dyno booster starter moter to drive these hotrod piston port racers up to 7000 RPM on the dyno, where they could finally go to WOT, hold their own and be tested! Also a 20 year old Black Magic 800 triple (made out of three 500 twin cylinders on an old triple crankcase). Great fun for me since we haven't tuned any of these for many years!

9/19 H.Kirsch and T.Koz here w/ Glenn Hall tuning two D&D Cat 1200 twostroke Boondocker turbo systems. The smell of VP import 120 octane gas still permeates the dyno room 10 days later...

9/21 Full Power Justin dialing in a PS800 SkiDoo triple.

9/23 Great grampa 70+ Paul Cross (father of Tripod Dan) tuning his rat-rod Cat 6000/ Wildcat 700 mod. I first met Paul about 40 yrs ago when he came into my welding supply to see if he could borrow a small cylinder of oxygen. He wanted something small enough to hide beneath his snowmobile jacket, unzipped just enough to try to squirt some O2 into the single carb of his sled just to try to beat up on a snowmobiler pal of his. I can't recall the outcome of that adventure. But getting off the subject of dyno schedule, the first time I met Terry Paine (who would eventually marry DynoTech Debbie and later take over Bender Racing when Tim Bender decided to go NASCAR racing) maybe 30 years ago he, too, came to my welding supply to borrow a small 20 cu ft O2 cylinder and 10' of hose. His cousin had just bought a Dodge Superbee 383 magnum and Terry convinced him that they could really make tire smoke if they ducted O2 into the air cleaner! I fixed Terry up with a loaner bottle and hose--they ducted to hose into the air cleaner snorkel and drove off to enjoy the extra HP with Terry riding shotgun, grinning, with the O2 bottle in his lap. Five minutes later, the Superbee was back in my parking lot--idling on maybe seven cylinders and with the hood buckled from the exploded air cleaner. True story, with no embelishment needed!

9/24 Brad Linsey trying to figure out why his Hooper 1108 triple asphalt sled would lay down after half track. Once again, vibrating carbs were the culprit, causing foaming race gas and float bowls going dry. We fixed this today by strapping 5 lb of weight to the carbs.

9/27 Tim Huber, Cat 1200 twin trying to tune for max power for outlaw drags. So electronic gremlin is haunting this machine, and as happens occasionally the gremlin could not be found. 

9/29 Canadian Dave Hutchinson coming to see why he keeps detonating pistons on his HTG 1000 triple. once again, vibration was the culprit...causing poor fuel delivery into the carbs...we tied my 6lb pinch bar to the carbs, and fuel flow returned to normal. Beware stiff motor mounts, and imbalanced or out of true crankshafts!

10/3 Bob Brown trying to eliminate deto on a custom SkiDoo trail hotrod. jetting was the culprit on this one--.52 won't cut it on pump gas on these engines

10/10 Greg Van Heulen CFR1000 tune

10/19 D&D Dale & Glenn dialing in Kevin Hunter's Crossfire 1200 turbo--over 415hp with no clicks of deto. Also doing their own muffler testing on a prepro XF1100 turbo...

10/22 Dave Peterson's FPP Nytro turbo bone stock engine with boost = 325hp, also Jack Lloyd tuning a Yamaha FPP modified GPX433 free air vintage racer 

10/24 Boondocker tuning a Cat 2012 procross 800 w/ RKTek 925 big bore. Hope the DynoCams will be running! good power, dyno/tuning data is posted on members' section.

11/4 Dead one Dave tuning his new stock engine 2012 Procross 800 for max power for hilldrags.

11/7 WakPak Joe tuning a 1000 twin for hilldrags.

11/11 Sean Weir with a SnowCross 600 mod SkiDoo. Also Tom Bachly with a new 2012 bone stock SkiDoo 600RS, tuned for max HP dyno test and tuning info posted on members' section now.

11/12 Bill Gregory, SkiDoo 800 triple mod, dialed in a dandy timing curve on his MSD.

11/19 Don Zuzze PCV tuning two seemingly identical F6's (required totally different maps) and one F1000.

11/20 Rob Lathrop fine tuning for max HP on a full mod SkiDoo Trigstad 600 twin. Also Dave Lathrop with an improved stock SkiDoo 800 twin also getting ready for hilldrags. our new data acquisition system gives us a "Density Altitude" reading while we test. DA is a combination of baro pressure, temperature, and humidity (water grains per pound of air). With max power carb dyno jetting created here at a given DA, we can then use a Kestrel 4500 Racing Weather Station wherever you're racing to get accurate DA. Then using just the altitude half of a Mikuni Pocket Tune sliderule, perfect jetting can be maintained. Pro racers tune at DTR then with this system perfect max HP jetting can be maintained froom sea level subzero to mountain racing out west.

11/21 D&D Dale & Glenn tuning for high safe pump gas HP with production F1100T. Muffler testing, HiJacker testing, all with stock turbo outlet pipe.

11/26 anonymous tuner, top secret today.

11/27 Mark Fisher getting ready to hilldrag with a Sherlock Crossfire 800/ Jaws race pipes.

11/28 TurboDynamics Ben with his production F1100T, testing his various ECU tunes all with high flow turbine outlet pipe and stainless steel fairly quiet muffler. to be posted soon

11/29 greedy Bill Swoyer looking for even more HP out of his CrankShop 1500 hilldragsled. Larry-this sled needs to run in the AmSnow Adirondack Shootout on 12/9! We have an all-motor class in the Lakeracer division!

11/29 WakPak Joe with his 1000 twin again, looking for more HP.

11/30 Vintage oval racers Brandon Hadley and Al Young tuning two race sleds--a SkiDoo 340RV and a Polaris TX440 for Eagle River.

12/1 Mad Canadian Gerry Prosser (Bender Canada) PCV tuning an EXUP Apex with Yamacharger, and trying out stock vs MBRP vs Bender vs D&D mufflers. this data may be posted on members' pages in later December. 

12/1 D&D Dale testing stock 2012 Apex then upgrading HP with PCV, D&D Stainless muffler, and high flow airbox cover and high RPM carb inlet boots. will post this after the 12/9 Adirondack Shootout  

12/1 PM Dale demonstrating big HP on their trail ported/ single pipe 2012 ProCross 800. will post this after the 12/9 Adirondack Shootout

12/4 Gary Foster tuning his 07 crossfire 800 with D&D shim kit and porting by Dale Fredericks. the dyno cold intake air refrigeration was necessary to get accurate winter tune today. outside air was 55 deg F, so intake air was chilled to 25 degrees.

Tuesday, August 02, 2011

DynoTech : New equipment thanks to Kevin Cameron

Coming next: a $2200 coolant flowmeter to integrate into our SuperFlow 902 data acquisition system...

I subscribe to Cycle World magazine primarily to read CW Technical Editor Kevin Cameron’s (KC’s) monthly TDC (Top Dead Center) column. Recently he did one on turbulence, which relates in part to the "Bathtub vs Shrinkwrapped heads" info he provided us (scroll down in the blog section to read that). So I asked KC to provide us an update article to explain turbulence and its benefits, both in snowmobile combustion chambers and cooling systems. That five page article is now posted on our subscribers' pages.

There are times when we question a stock sled's ability to properly cool itself, much less one modified with higher than stock power levels. Last year, Boyesen sent me a billet water pump impeller for a Polaris twin that I would like to test. Joe Dispirito has made some billet thermostat housings that he says reduce Polaris engine temperatures in the field. This new coolant flowmeter will enable us to assess both, and estimate the velocity of the coolant flow, in ft/second, through the heat exchangers. The flowmeter is a short 1” diameter turbine with a long cable which will enable us to test coolant flow on the sleds, with coolant flowing through the sleds' heat exchangers.

And how about Kevin Cameron's opinion of the most ideal, highest power, highest turbulence producing squish clearance at .027" even on two-stroke roadrace bikes that endure minutes at WOT? Certainly controversial for those of us who are used to seeing .050-.060" squish clearance in sled engines modified for maximum power. Sure, there are lots of powerful engines winning races with .055” squish. But couldn't all of those engines make even more power with pistons .005" from kissing the heads, and squish band width and timing optimized on the dyno? From what I've seen here, yes!

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There are some 30-odd articles by Kevin Cameron in our archives. When you scroll down the subscribers pages to the 37 scanned copies of the early printed DynoTechs, you will find in most of them a technical article (TCD-The Cellar Dwellar) by KC on all things two-stroke and snowmobile engine performance related. Many young sled hotrodders who are DTR members make a mistake by ignoring the "old stuff". But in those old scanned issues in the archives is a treasure trove of meaningful information. It may not be too exciting reading about obsolete 650 piston port triples, 110 HP Wildcats, 75 HP Phazers, etc but most of what we have an understanding of today was learned back then, and documented in those scanned printed issues.

We've all been fortunate to have Kevin Cameron to help explain things that have baffled and bewildered us ever since we began testing and printing results back around 1988. Even today, just when we think we "know it all" (tongue-in-cheek), something will come along that needs explanation by KC and he still takes the time to help us to figure out what's going on. Turbulent flow of air and coolant is a great example of that.

I became acquainted with Kevin Cameron about 24 years ago. Kevin had built a Honda Hawk roadrace engine for a New Englander named Ed Abdo. The mods included a set of Keihin flatslides Kevin had converted to downdraft operation with stock floatbowls machined off, and remote floatbowls added. Ed had been unable to get the engine to run cleanly--too rich or too lean everywhere. In 1987 (before the invention of the DynoJet inertia bike dyno) C&H Dyno Service (that's what we called it before it became DynoTech Research) was one of the few dyno testing facilities that could accommodate a motorcycle engine in the bike’s frame using splined trans output shaft (never call them countershafts!) adaptors to connect engine to the dyno absorber. So Ed Abdo came here out of desperation. He showed up here with a shoebox full of every tuning component Keihin made for those carbs, and Ed and I dyno tuned this gurgley thing--madly swapping pilots, air jets, needles, tubes, mains etc on those custom carbs until they worked perfectly, and made lots more HP. At the time, I think Kevin was most impressed because the changes we made to correct the mixture on those carbs in some cases contradicted the Keihin carb manual! Two monkeys with an instrumented dyno, and lots of tuning parts can create excellence!  But we kept at it until we had relative perfection. And the actual airflow/ fuel flow data was as intriguing to KC as well as the output shaft torque and HP.

Kevin Cameron subsequently agreed to become “Technical Editor” of my DynoTech newsletter, providing engine-related technical info that helped educate us then-novice sled tuners. About the same time, he became a consulting engineer for Texas high schooler Colin Edwards' (who grew up to be two time world Superbike champion and now races for Yamaha in GP-1) motorcycle roadracing team, which was financed by actor Woody Harrelson. The race team and Kevin came here several times to test and tune incredible Yamaha TZ250 (90ish HP at the output shaft) bikes. Those were enjoyable, educational (as much for me as for them!) times.

Over the years, Kevin would occasionally even consult with me on particular issues about what I might have experienced on my dyno. He appreciated my opinion on things, since he suggested that I had a unique perspective--virtually everything I knew and at least partially understood came from actual dyno testing--not clouded by preconceived notions and opinions. I was honored to receive an acknowledgement in KC’s 176 page “Sportbike Performance Handbook” (MBI Publishing) in 1998.  

Read Kevin’s piece on Turbulence, and engine builders please experiment with those squish bands! It should be done methodically on a repeatable dyno with copper tube connected to the engine to listen for knock. There’s surely hidden HP there! It’s great fun when a racer comes to test with a box full of chambers and a means to quickly change timing. Stay tuned this season forward as we examine and document the advantages of high velocity in allowing/ creating higher power levels in both trail and race engines.

Sunday, June 05, 2011

DynoTech : Spring- summer 2011 schedule etc

4/20 Chukaroo Hamrah/ Steve Petshke very powerful PS1000 asphalt drag engine.

4/21 PAer Marty Walborn, full mod Banshee drag quad w/ billet 850cc engine.

4/21 pm Dave Weisner/ Steve Mazolla 936cc Storm asphalt drag engine

4/22 Ron Cooper SkiDoo 600 mod water racer

4/22pm Ryan Muehlig Polaris 600 mod water racer

5/7 TR McGinnis Yamaha YFZ450 making more power with Wood drag exhaust. Photo shows how we dyno tune quads, with measured fuel flow gravity fed from a Holley float bowl to the carbs.

5/16 anonymous racer tuning a crankshop SkiDoo 800 twin full mod

5/25 Gene Hurin w/ HTG 1000 triple improver, testing the new Lectron 50 mm carbs. Gene was the victim of stale C14--the worst of the worst when it comes to losing it's light ends--he bought it from a supplier in Albany NY out of a re-sealed 50 gallon drum, came here and on the first pass four-corner seized it at a "safe" 12/1 and 80 degree F coolant. So now we know that it was net lean-to-death 16/1 in the combustion chamber, then the globules of unvaporized fuel were vaporized by heat and burned in the pipes, fooling the wideband measuring A/F ratio at the pipe outlet. So piston was fixed, and Sunoco Maximal from a full new drum was used, no change in carb settings, ran 20 passes with even leaner power jet settings down to 13/1 and no problem. I like those new 50mm carbs too!

5/27 Chad Andolina w/ SkiDoo 800 triple asphalt sled

6/3 Mark Cross Banshee 350 mod field drag quad, added 12 hp with maxed out jetting/ timing!

6/3pm Tripod Dan Cross dyno tuning his HTG1250 triple--added 20 hp by removing bad race pipes and installing pipes from his PS1000 engine.

6/4 Dave Waters, KTM950 flat tracker w/ intake restrictors, featured in last month's Cycle World

6/6 Matt Wise, Yamaha SRX600 imp stock

6/7 Kevin Hazel Harley XR750 flat tracker w/ intake restrictors

6/12 Ken Coolbeth (AMA #2) from CT, 2011 Kaw KXF450 flat track modified engine--were slower on the track than the 57hp dyno sheet the engine builder gave him, made 50 HP here, local bike engine modifier is redoing the engine, expect 60 real HP next time.

6/13-16 Glenn Hall w/ D&D Z1 Magic Turbo system, turbo engine testing different tubochargers and throttle bodies. 506 HP at 41-42psi boost--will post the actual dyno test results...

6/17 Frankie Amalfie Vmax SX 700 stock engine w/ Hauck Husher pipes

6/17 Jim Chittenden ZRT600 light mod asphalt racer w/ Aaen pipes

6/18 Chad Andolina back again with new Jaws race pipes for his SkiDoo 800 triple mod asphalt racer

6/24 anonymous racer with Crankshop 800 twin race engine

6/25 John Dandrea w/ D&D SS 900 Firecat, winter tune with cold dry air system 80 degrees and humid today, used cold air system to feed 30 degree dry air to the intake, Boondocker "internet map" was too safe 171hp at .75 lb/hphr, we tuned John's F9 EFI to pump gas safe 174hp at .70 and also a lakerace map 179hp at .60

6/26 Alex Izzo with Triumph Daytona 675 w/ home-built Rotrex supercharger system--tuned PCV to 155 RWHP at 11.8/1 (took about three hours to create a boost-friendly map).

6/27 Jesse Calvert F7 stock dragracer

7/5-8 gone fishing with my 12 yr old son Marty.

7/10-7/13 AMA #2 Ken Coolbeth Kawasaki 450 flattrack racer Ken had this engine modified, got a 57hp dyno sheet from the builder, bike was slow at the track, brought it here with local bike engine modifier Ron Jewell (RLJ Racing), dyno tested here at 49hp (less hp than stock)...Ron tweaked the ports, lowered compression, modified the exhaust and on 7/13 made 59hp. Now the bike is fast.

7/16 Sean Ray new FatBoy 96" getting normally aspirated baseline fuel numbers on his new stock H-D Fatboy 96 cu in engine with much larger Delphi injectors. This was to prepare for installing one of his Garrett ball bearing turbo systems with new Power Commander V with new boost/ intake temp sensor. Planning to display the bike at Sturgis w/ DynoJet. Expecting 200 RWHP with 96 cubic inches, hence the need for larger injectors.

7/16 Make Hatcher RLJ Honda CRF250

7/19 James Ristoli/ engine builder/ tuner Floridian Ryan Kelly two Suzuki 600 roadrace bikes, tuning for max power with Yoshimura EFI ECU/ software.

7/30 Tripod Dan testing an unhappy PS1000 engine

8/5 Sean Ray using CycleDyn to Power Commander/ power Vison tune his new all black FatBoy stock 96" engine (turbo cams and heads) with an all-black turbosystem he manufactures (SeanRayTurbosystems). He was planning to display/ demo the bike with the DynoJet guys at Sturgis, took him 30 minutes to create a perfect tune, made well over 200hp here, then 214hp out at Sturgis without breaking a sweat. fatboy ran 10.4 and 132mph at NYIRP

8/9 Brad Crocker tuning Pol 600 twin Flannery mod, DynoPort pipes

8/10 Justin FPP tuning on an Etec 800 turbo

8/18 Sean Ray tweaking on a PS800 polaris twin, cams off.

8/25 Billy Howard's bad-ass 2012 Cat ProCross 800 (incredible results posted now)

8/28 Sean Ray tweaking more on the PS800 polaris

8/29 John Diangelo dialing in a new MSD/ new bigger FPP turbo on his SkiDoo 1000 triple

8/31 Barry Taggart, PS1000 Yamaha triple FPP

8/31 Barry Taggart IS700 Yamaha triple FPP

8/31 Jim Chittenden Cat ZRT600 mod

Friday, June 03, 2011

DynoTech : Equipment upgrades!

Here's the aforementioned dyno starter drive sysem! Now we can remotely start engines from either driveshaft. That's a Polaris sled ring gear bolted to a custom fabbed aluminum flywheel. Gone is the $550 German overrunning sprag clutch (that needed relacing every few year$) that used to belt-drive the right hand shaft from the original Cummins diesel starter seen mounted below.

Now I've converted the original big starter motor to being a "booster" to help small, or poorly carbureted race engines spin the shafts/ dyno absorber up to whatever RPM they begin making power at! Those who have tuned small engines on big dynamometers know how critical part throttle tuning is to get the engines to spin themselves along with the drag/ weight of a big absorber. And some 340/440 race engines might not even "come on the pipe" until 7-8000 RPM. Sometimes, out of desperation, we would squirt N2O into small race engines to get them to rev up from idle on the dyno. But now, I have mounted a small 5-rib Whipple supercharger pulley onto the main dyno driveshaft (seen close to the guard near the absorber). That pulley is driven by a serpentine belt/ belt tensioner and larger 6" diameter ribbed pulley mounted on ball bearings below. That large ribbed pulley is driven by the big original starter vis a small driveshaft, and is engaged with a magnetic clutch. Now, when the big starter button is pushed, it will overdrive the dyno absorber and shafts up to 9500RPM. Bring on those little vintage race engines!

Also note the slick machine-lettered aluminum plate fitted with Jiffy-Tite fuel quick-couplers, showing fuel in and out of each flowmeter (meters won't read if plumbed backwards!), organizing that awful rats-nest of hoses, making EFI hookup to sleds with bypass (requiring subtracting bypassed fuel from gross flow) easier than ever.

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Here are the three walkin freezer compressor units that are thermostatically operated from the dyno control room. Below is a photo from inside the cold room, showing the three condenser units--each connected to one of the compressors outside the left wall. Just visible behind the condenser stack is a 10" diameter air intake pipe that draws "makeup" air from the roof of the building. As the engines consume air (via an insulated duct from the opposite wall to the engine's airbox inlet), replacement air is drawn in to the area directly behind the condensors. Note the PVC pipes from each condenser which carry away the water that condenses as humid air is cooled.

Sunday, February 27, 2011

DynoTech : March schedule, update

2/25-3/2 reengineering, updating dyno drive system. The big dyno starter drive is mounted to the high speed dyno drive shaft used by 99.99% of the engines we tune. From experience I know that the "blower" (Gates PowerGrip toothed) belt drive we to reduce absorber speed 33% is on the edge at 500+ HP (remember how we noticed it literally smoking hot after each of Justin Durand's Vmax 4 turbo dyno runs). So, we must on occasion remove the belt reduction and drive the dyno absorber at engine output shaft speed. But in doing so we lose the function of our electric starter.

Don Emery and Tommy McConkey are planning to come back with Tommy's big four cylinder radar run sled (they made the first 500+ HP dyno run here with n2o and have run 192mph with n2o). This time, they have made the engine bigger and stronger, and engaged turbo madman Gus Bohne to create a turbo system for this engine with hopes of even more power.

Since this huge engine has only pull-start, and will have to be run with the absorber at crank speed, I'm creating a high speed electric starter drive for the main drive shaft. This requires making some custom parts, and chasing around for a high speed automotive starter with the largest possible drive gear, hence the extended down time.

3/4 Andy Caffaro PS1000 Polaris

3/7 Ken Pielechowski PS800 SkiDoo

3/10 DNE, Tommy McConkey and Gus Bohne tuning Tommy's monster two stoke quad with huge turbo sysem, hoping for enough HP to add 10 mph to his 190mph radar run sled

3/11 Barry Britton & son, tuning two hilldrag sleds

3/13 (rescheduled) Polaris ProR 800 tested with Aaen, BMP, DynoPort, and SLP pipes (and PCV maps created where necessary). Then if we find good power improvement, Casey Mulkins will install the cylinder shim/ revised head again. finally great success with pipes/ shim kit! results posted!

3/15 Sean Dingman/ Todd Hogan SkiDoo 800 twin hilldragger

3/24 Dan Cerio tuning a Cat 1000 hilldragger

Thursday, February 03, 2011

DynoTech : current events with 800 stockers &tc

 We're still waiting for pipes to test on the ProR800--SLP is doing their flatland field testing this week before shipping, and BMP and DynoPort should be shipping their production stuff soon. As soon as we can get pipes from them, Casey Mulkis is ready to test a stocker, and one more time with the shim kit.

Billy Howard was scheduled to test stuff he's acquired for the Etec800 but his field testing on his long plowed snow strip has shown strange issues--one 1/4 mile blast with good acceleration, followed by another short blast with poor acceleration, underrevving. So we've put that session on hold until we figure out what is causing the grief.  My pal Rusty from Rapid City SD is experiencing the same problem with his bone stock Etec800 at 6000 ft altitude. We're thinking now that it is exhaust temp creating this strange loss in power after some reasonable time at WOT. The probe in the muffler may be getting up to some temperature, and then the ECU drops the power level and causes underrevving. What causes the drop the power? Retarding the timing would only increase the ex temp, making the pipe even hotter. Adding fuel would even help Billy's sled, which is boarderline lean with the exhausts he's testing. So could they be lowering the exhaust valves slightly to choke off airflow? At any rate, Billy has eliminated the power dropoff by advancing his ignition timing with his buds computer. Rusty is planning to do the same with his stocker, and test it this weekend. Now, advancing the timing reduces exhaust temp (the fire stays inside the combustion chamber instead of blowing out the exhaust ports, hopefully making more cylinder pressure and torque), and maybe Billy advanced his enough to heep the muffler temp below the threshold temp. We'll know more about this phenomenon next week, and hope we can reschedule the Etec800 test session. 

Thursday, January 06, 2011

DynoTech : cool engines = hot performance

When it comes to making best HP without detonation, cool engines rule. We need just enough heat in the engine components--crankcase, crankshaft, cylinders, cylinder heads and pistons to allow the fuel to vaporize. Infamous "cold seizures" are the result of imperfect fuel vaporization while running under power with too-cold engines, which creates excessively lean mixtures that cause the pistons to grow too big and stick. Unvaporized fuel in too-cold engines can go through the engine without burning in the combustion chambers, which means that a nice mechanical 11/1 pounds of Air/Fuel ratio can become, net, 11/.6 or  18/1 (that portion of the fuel which manages to vaporize and burn in the chambers) which can detonate and/ or cause seizures. And those big lava lap-like globules of fuel, most of which eventually vaporizes and burns inside the exhaust (resulting in safe-appearing wideband A/F readings)  can splatter against sparkplug insulators, shorting out the spark, causing misfire.

Some engines need lots of heat to run cleanly. Among worst were the Vmax 4s with those awful racked Mikuni carbs. Those who tried running with the 120F thermostat removed were rewarded with 100F coolant temp and continual gurgling from poor vaporization. That engine/ carb combination really needed 120F coolant temp to run cleanly.

But most engines will run cleanly and happily with 80-100F coolant temperature, and will make way more power than they will at 150F. And cool (not cold) engines are much less likely to detonate with max power A/F ratio.

Some Dragon 800 owners complain, bitterly, about excessive (150F +) coolant temperature while riding. If we can get that engine to run at 100F or even cooler, it will be a better machine. One Polaris tuner has ordered aluminum extrusions with which to make auxilliary tunnel heat exchangers. Joe from Boyesen Engineering sent me a billet prototype high-flow water pump impeller to test. If we can increase coolant velocity and turbulence through the engine, and supplement heat exchanger capacity, 100F or cooler is surely within reach!

reprinted from a past blog entry "Bathtub heads vs Shrinkwrapped heads":

I subscribe to Cycle World magazine primarily to read Kevin Cameron's monthly one page TDC column, and to try to absorb detailed technical articles he writes that appear in about every other issue.

In a past CW issue, Kevin addresses coolant velocity in cylinder heads. According to KC, turbulent high velocity coolant is vastly more effective in removing heat from combustion chamber "domes" than lazy slow moving coolant. Worse yet, is any area of stagnant coolant that rests against the domes' coolant side surfaces with slow or no movement which can create dangerous detonation causing hot-spots. 

Kevin describes large coolant volume cylinder heads as antique "bathtub" design. Conversely, he describes modern sled cylinder heads (like some SkiDoo models) as having a "shrink wrapped" appearance where the diecast cylinder heads' outer covers closely mirror the shape of the combustion  chambers. Shrink-wrapped covers create small but ample passages for high velocity coolant flow over the combustion chambers.

Some of the aftermarket snowmobile cylinder heads I see on the dyno look like bathtubs to me.  Most "billet"  head covers are large rectangular structures that appear to hold lots of coolant, exactly the opposite of what would create high velocity turbulent coolant flow over the internal surfaces of the combustion chambers.

On typical dyno tuneups especially this time of year it's more time (and cost) effective to dyno sled engines with their own coolant, letting the 7.5hp roof mounted dyno room blower cool the engine between dyno runs. To maintain consistancy, I like to measure head surface temp with an infrared gun before each dyno run. On most sleds, head surface temp runs about 20 degrees F lower than coolant temp, but this is not as important as doing each dyno run with similar engine and pipe temperature.

What I notice on some aftermarket cylinder heads is that ending surface temp (after 10-15 second dyno runs) is sometimes much higher than what we usually see with stock heads. In the past I have dismissed this difference in being caused by different material finish (shiny machined and anodized or powder coated billet instead of die or sand cast surfaces) causing different infrared gun readings. But after digesting Kevin's  info I'm thinking that we may be  experiencing the bathtub syndrome.

How bad is this?

My favorite example of stagnant coolant was Tim Bender's experience with an Exciter FIII oval racing engine over 20 years ago. Kevin Cameron had suggested to Tim that the golf-cart-like transfer ports on the Exciter engine limited its potential. So Tim decided to widen the engine to allow room for larger transfer ports that he would create out of material welded on to the sides cylinders. This meant having the Crankshop build him a wider crankshaft, then saw a crankcase and cylinder head in half, then weld in an inch or so of material to allow bore spacing to be wider, accomodating normal-size transfer ports.

Tim's problems began when the one-piece cylinder head was widened and welded back together. The Exciter 570's coolant normally enters the front of the head in the center, then is forced around each combustion chamber surface, then rejoins as it exits the rear center of the head at the thermostat housing. However the widened and rewelded head provided  an unintended short-circuit for the coolant straight through the center of the head from front to back without being forced around the combustion chambers. Unbeknownst to Tim and me, this allowed stagnant water to lay on the combustion chambers instead of flowing over them. Trouble was lurking.

On the dyno, even with lots of water flowing to cool the engine, we never could create low BSFC without detonation. But the engine made more HP than before and Tim was anxious to test the engine in his race sled before going to the annual big oval race at Eagle River.

I went with Tim to a nearby frozen lake where the night before he had snowblown an oval track on the shallow end. When he began doing laps with his dyno-tuned engine Tim encountered detonation with the same jets, same gas as we had dyno'd with the day before. Jets that were dandy for 15 seconds on the dyno were causing deto on the track after 20 seconds. The 48mm carbs required about 15 sizes larger jets to be deto-free, and that extra fuel drowned the HP added by the larger transfers. This was perplexing to both of us. At the end of the day, Tim's high HP wide engine was no faster than the narrow golf-cart Exciter race engine he had run previously. Why the deto? With his other race engines, winter dyno jets were within a few sizes of what he needed for 20 laps.

That evening, one of us remembered the widened cylinder head. I like to think that I came up with the solution to the problem, but it probably was Tim. One of us called the other, and we discussed the possibility of a problem with combustion chamber coolant flow. Tim went to the shop at 10pm, and upon inspection found that there was an open passage in the widened area for coolant to flow directly from the front center head inlet to the rear center outlet! He mixed up some Devcon epoxy filler and goobered that unintended passage closed. As intended, coolant would once again be forced to the outsides of the head, pass over the chambers then rejoin at the rear before exiting the engine.

The next day back at the lake, Tim was able to jet down all of the 15 sizes (and then some) and the HP was back, deto was gone. More races would be won.

Bottom line--stagnant coolant was surely the culprit. According to KC, when coolant boils and creates a steam pocket anywhere around a combustion chamber, detonation is sure to follow quickly even with the safest A/F ratio.

I'm not suggesting that all billet replacement heads are low velocity bathtub design--in each case I don't know what sort of internal passages were created by the person who programmed the milling machine to carve out the "tub". But my opinion is that before an aftermarket head is installed in might be good to compare coolant volume between the stock head and the replacement head. If the replacement head has larger capacity than the shrink-wrapped stocker I would question the design and ask why the volume is greater. If the answer is "to help cool the engine".....

The factories' sled engine designers surely use dyno software that measures coolant flow in GPH, and that figure along with temperature rise in the coolant around each combustion chamber is necessary to correctly design the cooling passages in any cylinder head, either OEM or replacement.

When it comes to snowmobile cylinder heads, cool-looking and big is not necessarily better.

Wednesday, December 29, 2010

DynoTech : January/ Feb schedule &tc

12/30 Ross Reynolds from NH, two mountain motor Cats

1/3 Richie Meyers 518er looking for more HillDrag HP

1/4 Joe Shear XF1000

1/5 Tom Anthony IQR tuning 

1/6 Jake Jenkins/ Dave Dillenbeck F7 big bore ]cancelled]

1/7 Kevin Atkins XF1000

1/8 Pat Paradiso trail mod Dragon 800 w/ various pipes

1/10 Jake Jenkins/ Dave Dillenbeck F7 big bore

1/11 Joe Shear F1200 lakeracer w/ boondocker n2o

updates coming  1/23

1/12 Rob Schooping/ John Clarey HTG1200 triple

1/14 Tim Winslow & Todd Hogan 800 promod hill drag sled cancelled

1/20 Dave Patrick F7 pm Steve Falmond F7/ Black Magic 800 for boondocker tuning

1/21 Koz Bros XF800 improver tuning 

1/22 Jeff/ Vinny/ Danny Cerio Hooper TCat 1400 tune

1/22 PM Bill Swoyer cameras off

1/23 Casey Mulkins Dragon 800 tuning, trying new Aaen single pipe

1/24 Mach Z nano N2O tune, cameras off

1/25 Koz Bros tuning Sherlock Improved Crossfire 800

1/26 Tim Winslow and Todd Hogan  promod hilldraggers

1/27 Carl Theriault Crossfire 1000 pipe shootout, Z1 tune delayed by new england snowstorm 

1/28 Casey Mulkins back again with ProR 800, pipes, shim kit once more delayed by lack of pipes 

1/29 HillBilly Howard, Etec 800 stage tuning with Bobby Donnatelle cams on delayed by possible lack of fuel to make extra hp at low temp high baro 

2/2 Full Power RX1 extra large turbo tune  cancelled due to Justin having the flu

2/3 Todd Hogan, more hilldrag sleds to tune cancelled due to weather

 2/4-5 Carl Theriault Crossfire 1000 pipe shootout, Z1 tune cancelled

2/6 three flattrack bikes, tuning for Daytona

2/7 Ryan Kehl, Crossfire 1000 pipe shootout

 2/8 AM Heath tuning a Jaws pipes 1080 triple,  Nate McCoy, going for big HP on a XF800 mod

2/16 Boyesen Reed evaluation on stock XF800 w/ Todd Hogan, cams off

2/21 Turbo Dragon 800, attitude controller tune

2/23 ProR800 pipe test, cylinder shim test w/ Casey Mulkins

Monday, December 13, 2010

DynoTech : broken dyno drive components...

For the next few weeks or so, all 400 plus HP tuneups are on hold. The following photos show what is left of my $1000 big driveshaft.

In my blog schedule I facetiously suggested that last weekend after the Shootout, "OSP Jim and crew [were coming here] trying to break my dyno....". I won't be making jokes like that anymore!

Saturday afternoon, OSP Jim and madman driver R. Dustin came to demo the power of Shawn Burke's Adirondack Shootout record setting turbo Nytro (anyone who was at the Shootout knows it really didn't need much dyno tuning), but we never got to make any big power with the Nytro before the steel molecules in my big driveshaft got tired of holding hands. While loading the engine at 8500 RPM in preparation for our first dyno test, we felt a 1/2 second shudder followed by a loud pop and the engine was against the rev limiter for a fraction of a second before being shut down. The driveshat had separated at both ends--from the rubber vibration dampener at the engine, and the automotive ujoint coupler at the absorber end.

Fortunately, the orange colored driveshaft loop did it's job, and the roof of my building is dented by small parts but unpunctured. But there was a violent 360 degree spray of bolts, u-joint bearing caps and bearing needles that created many new holes in the ceiling tiles, walls, and light fixtures. And there are surely some IED-like steel shrapnel that I will find, rusted, in the parking lot next spring. 

The taper end on Shawn's nytro is bent, but that working end, splined to the end of the three cylinder crank is replaceable from the side of the engine.

But most importantly no one got hurt. I will keep what's left of the driveshaft to explain to people that come come here why we never enter the dyno room with the engine under power. 

Do I need a stronger driveshaft? Nope--it wasn't fatigue from too many high power sled engines (the shaft is designed for 500 lb/ft continuously), but operator error that created this havoc. Trying to assess this mess, like a forensic detective, I think this is what happened...

Torsional vibrations--impact gun-like forces that create havoc with crankshafts/ crank tapers/ clutches appear to be extremely violent on three cylinder four-strokes when boosted to many times their designed torque levels. Monsterous torque levels can cause those engines' cranks to wind up and unwind, creating torque spikes up to 10x higher than the engines' average torque. This can cause premature wear on clutch parts, and slippage of crank tapers creating wedging of clutch tapers or even worse fretting enough to melt and weld the steel on the crank tapers! Recently FPP Justin was here with a high-boost 4tec that after maybe five 400+ HP tuning runs, and spot welded it's crank to my SkiDoo dyno adaptor. I was able to remove the adaptor from Justin's crank, but there were some small chunks of his crank taper melted and welded into the female taper on my steel dyno adaptor. But I have had very little trouble like that with the many high boost four cylinder Yamahas and two cylinder Z1s tested with big torque. There just seems to be more torsional vibes with the big triples.

I was hoping not to do unintended taper welding with the OSP Nytro. So when R. Dustin showed me a light coating of moly lube on the crank taper (they do that to prevent stuck clutches), I decided to not clean it off, and see how that might help prevent taper galling during dyno testing. I installed the grade 8 dyno adaptor bolt with all the torque my IR 1/2" drive impact would put out, and attached the drive shaft. But when we began testing--loading the engine at 8500 there was some unhappiness with the dyno trying to control things. The SuperFlow dyno is completely automated--if you set the control to hold the engine at 8500 before beginning at test, it will try to do that regardless of whether it' 50 or 500 HP there. In this case, the dyno seemed to obtain the desired 8500, but then it would misfire like tuning was poor but Jim saw on his laptop monitoring the stand alone that it was against the rev limiter. But the dyno measures dyno speed, and Jim was measuring engine speed so that difference was probably my coupler slipping on the crankshaft taper! But that didn't register with me (never had that happen before), and it should have. Brain failure one is I should have removed my adaptor, cleaned the tapers and started over. But we tried again several more times befor the catostrophic failure, and this time I believe the torsional vibes/ slippage caused my tight crank bolt to begin backing out creating even worse slippage, and severe out of balance condition at the engine. And that perhaps created more strange, almost indescernable vibrations that were causing the four bolts on the dyno end to become loose, and eventually completely remove themselves from the adaptor and fly away. So my second brain failure was not going to check the condition of the driveshaft fasteners prior to each attempt to test. All four nuts flew, as did the lockwashers and bolts. Nothing broke, the fasters just loosened up and removed themselves in just a few seconds of operation, then flew in all directions like the square pieces of a pineapple hand grenade. I've done this so many 1000s of times without fastener issues, I ignored them at the worst possible time.

So OSP Jim will need to replace the Nytro crank end (hopefully only a few hundred bucks) and I will replace my big driveshaft. No need to redesign it, just build it again. But my cavalier assumption that what I tightened during setup will remain tight during the session is changed. And maybe now blue locktight on dyno shaft fasteners on these big engines will be part of the program for gonzo HP things.

And I must compliment the OSP guys on having the demeanor necessary for anyone who regularly races/ tests/ sells engines approaching 10hp/ cubic inch. Not everyone has that. Gaskets can squirm out, pistons can sieze, blocks can crack, rods can snap, and dyno drives can fail.  I don't know who coined the calmly spoken southern drawl phrase "parts is parts", but it's appropriate.

This innocent looking small engine coupler is about $600 worth of stuff- the eight hole Lord torsional vibration damper is a key component necessary to protect the engines from their own harmonics. And that center self aligning bearing (what's left of it) is designed for the linkage of helicoptor rotor assemblies. The aluminum part is custom made on CNC machinery. New parts are on the way here.

Tuesday, December 07, 2010

DynoTech : The first official DynoTech “BlowUp”

Queenan Racing's turbocharged Hayabusa asphalt drag sled on the dyno table

“Blow Up” is a commonly used euphemism among performance sledders to describe a seized piston—stuck in the bore because it temporarily grew bigger than the hole due to lean operation or deto. That euphemism annoys me because a stuck piston is not a “blowup”—it’s very non-destructive, non terrifying like a “blowup” would imply. I have always thought that the term “blow up” should be reserved for something more serious than a crankshaft that no longer turns, with something awry, but easily fixable inside the engine that is preventing normal rotation.

When funnycar racer John Force says he “blew up”, you know something way more violent than a stuck piston occurred.

In November I had my first real, true sled “BlowUp” on the dyno.

Terry and Mike Queenan had the Queenan Brothers Racing Hayabusa powered asphalt sled here to tune. This was to be a fun session—the fellow who provides parts and tuning for the Motec EFI system for Queenans (as well as the Al Anabi drag cars and bikes) was remotely monitoring the DTR tuning session from his home office in California, making fuel/ timing tweaks after each run via internet and observing the dynocams.

Creeping up on revs and boost (I think we were only running 11 psi boost and 410 HP) this fellow noted, watching data during each dyno test, that oil pressure had dropped a bit—perhaps due to rising oil temp? We cooled the crankcase for a few minutes before the next run. But what we did not realize was that a rod bearing on the big end of one of the engine’s aftermarket connecting rods was beginning to seize on the crank journal—perhaps smearing rod bearing material into the crank oil journals preventing total loss of oil pressure. This friction would eventually create heat that would in the next six seconds of boosted operation cause the rod to try to friction- weld itself to the crankshaft, then turn blue and eventually grab and snap sending parts flying.

On dyno test 10, we ran the engine up to 11,500 RPM and a sudden, loud snap accompanied a 7’ diameter ball of fire that enveloped the expensive area of the sled all the way to the ceiling tiles in the equally expensive dyno room!

This fire was accelerated by the 80mph air from the dyno air supply ducts—making it look exactly like one of John Force’s Funny Car “blowups” where headgaskets squeeze out and spew oil onto the headers creating one of those nasty, terrifying oil fires and an out of control funnycar. But in this case it was the rod cap blowing out the front of the Hayabusa crankcase, showering the cherry red header/ turbo with engine oil and creating the first DTR fireball.

I bolted from the control console, grabbing one of the 25 year old, but previously unused Halon fire extinguishers, and ran into the dyno room and with two pounds of Halon completely extinguished the fire. Terry and Mike Queenan were duly impressed with the speed at which Jr. Fire Marshal Jim was able to run from the control console, grab the the extinguisher and reach and address their burning sled. Halon is great stuff—today banned by the greenies but still said to be available, at a premium, from suppliers who have a stash of this stuff.

But with the fire extinguished, there was still a substantial amount of oil left on the dyno table beneath the sled….what if this sled was running down the dragstrip at 180mph instead of sitting on my diamond plate steel table?

 That unburned oil, instead would surely have been spewed and drizzled in front of the smooth rubber track with instant loss of traction and directional control! It’s one thing to have an engine explode (truly “blow up”) and shut a sled down, but the prospect of dumping oil directly in front of the smooth rubber track is terrifying considering what we all know might happen should a high speed sled/ rider encounter a guardrail or concrete barrier at 180 mph plus!

Fortunately, Queenan’s sled features a high tech multi-stage dry sump oiling system which minimizes unnecessary oil volume within the crank case and the sled also has a solid pan beneath the motor which trapped some of the oil from spilling out under the chassis. Without these features, the fire on the dyno table and the potential real-world scenario could have been much, much worse.

Why not add some sort of diaper-like oil catcher like the top fuel racers use? For them,  dropping oil mostly between the two rear tires is not a huge control issue, but NHRA is mostly concerned with downtime necessitated by cleaning up the mess. But sled racers with boosted four stroke engines approaching 10 HP per cubic inch will surely occasionally “blow up” engines, inevitably dropping oil directly in front of the tracks. It would be wise to deal with the inevitable spewing oil ahead of time.

From now on, people bringing heavily boosted engines to DTR must endure a pre-test fire drill.

Saturday, November 27, 2010

DynoTech : December Schedule, Shootout XXI &tc

12/1 518er Craig Horn, F12 trail mod for PCV tuning

12/2 Tom Anthony tuning an IQ600 mod from HTG

12/3 Koz bros PCV tuning two Cat 800 hilldraggers--one stocker on imp stock? cancelled

12/4 three new stock 800s Etec, ProR, and F8 for comparison w/ zero miles

12/5 Koz bros again with the two 800 cats, plus Glenn Hall tuning on Koz' new Xfire901 turbo

12/6-7-8 Dyno certification of the AmSnow DTR Adirondack Shootout sleds 12/7 tested SkiDoos and Polaris' then 12/9 will test Yamaha and Cats...12/8 doing minor dyno maintenance

12/9-10 off to the shootout

12/11 PM OSP Jim and crew dyno testing their turbo Nytro Lakeracer Shootout sled

12/12 AM OSP Jim and crew trying to break my dyno with their Apex drag sled

12/14 Bob Quigley dyno tuning a Z1 Lakeracer

12/15 jeff griswold htg d8 trailmod, PCV tune 

12/16 Chicken DT Jim back up to Hamilton Ontario Canada for a followup visit. anyone who hates dentist's needles, scalpels, scrapers, and sadistic dental hygenists as much as I do needs to visit Dr. Gabor Filo in Hamilton who (1) specializes in dealing with paranoia like mine (2) has the most pleasant and compassionate dental hygenist Jill and (3) has a $150,000 laser system that can painlessly remove not only cavities but also subgingival calculus! In the U.S. the FDA has not yet approved this dandy equipment which is also used in Europe and Asia, so if you must get your teeth cleaned beneath your gums in th U.S. you must put up with torture--or just drive to Canada and get it done properly and [nearly] painlessly.

12/17 Tom Anthony trying for big power on IQR600 mod, engine plate

12/18 Long Islander tommy santorufo tuning an F7 trail mod 

12/20 SLED Shop Inc, Presque Isle ME turbo SkiDoo 4tek tuning w/ FPP Justin Fuller

12/21 Nathan Ackland, Ontario Engine Tech 900 for Boondocker tune

Monday, November 01, 2010

DynoTech : November schedule &tc

Cold dry air is here, no matter what the outside temp is-- so we can tune EFI for winter use!

11/6 & 7 Jim Burlow & Torrey from Salt Lake City with their own EFI controller, testing on boosted and NA M1000 sleds.

11/8 Casey Mulkins w/ new ProRide 800 production sled

11/9 Tim Bounds Dragon 800 Boondocker N2O tune

11/10 Bill Capizzi two hill drag sleds

11/11 going to Hamilton Ontario to get my teeth cleaned of subgingival calculus with Lazer technology not approved in U.S. thanks to DDS lobby money. Thanks to Yamaha radar run madman Dan Jalbert for turning me on to this [supposedly] painless dentistry (Dan sells this equipment).

11/14 Dead 1 Dave Craiglow, new Stock Arctic Cat Crossfire/ M800 Single  PIPE SHOOTOUT

stock vs D&D, SLP, BMP, Speedwerx

11/16 Dick Ritter, Kennedy RV Powersports XF1000 BMP trail mod for Adirondack Shootout 

11/17 Don Pitoniak trying big throttle bodies on a XF800 trail mod

11/18 John Swan F7 big bore for Boondocker tuning

11/19 Gino 09 F8 Power Commander tune

11/20 tentative Casey Mulkins with the 2011 ProRide 800, custom cylinder shim kit/ custom Sean Ray stock head to match, expecting big HP to match the other 800s rescheduled to 11/29pm or 11/30pm

 11/23 Jamie Loson from Don's Polaris in Old Forge, testing the newest D8 flash with stock and with CPR twin pipes. wot fuel flow and ignition timing was no different than the earlier flashes, and could not see much midrange difference...so those who have the april flash should just stay with the PCV map you are using...and if Polaris has indeed added sorely needed midrange fuel you might note some midrange rich burble or laziness--then you can just reduce the midrange adder by 2-3% at a time until it's riding crisply. And as I predicted, those CPI twin pipes need CPR...results posted next... 

11/26 Rob Weiss RK Tech F8 for boondocker tuning, PM Justin Megliore D&D ported F7, single pipe and PCV tuning

11/28 Dead 1 Dave back again to test a new BMP Ypipe and SLP ex system on his XF800 stocker, plus some center section exhaust temp experimentation for stock dragracing. 

11/29 Bill Swoyer more hilldrag tuning

11/30 Joe McCarrow XP800 tune--PM Casey Mulkins with shimmed cylinders on the ProR800

Thursday, October 21, 2010

DynoTech : Finally, cold air being pumped into the dyno room

Friday, September 03, 2010

DynoTech : new dyno, cold air system, schedule update

The new 902 system is up and running perfectly. All new electronics, computer circuitry, and control console that took a couple of weeks to install properly. The operating system is quite different from the old 901 (24 years old), and has taken some getting used to. It's sort of like when my second wife moved in to my house 20 years ago, the first thing she did was move the silverware drawer from the kitchen cabinet next to the fridge to a different cabinet six feet away. 20 years later, I still open the drawer next to the fridge when I need a spoon.

SuprFlow tech Brett Williamson spent two days here showing me and Sean Ray the new system. I used my HTG Edge 1000 triple to verify the new system. Tuned to max power on pump gas on the 901 system, it made 225 HP. As Brett gauranteed, the engine made 225 HP on the 902. It's just math--torque and RPM, but it made me feel real good to see it myself on my own sled that has 100 dyno runs on the 901, and now 90 on the new system during training. And now instead of manually adding torque to make up for the 6.8% power loss created by the dyno absorber speed  reduction drive at 8000rpm (and then increasing exponentially) it's done automatically by the 902 computer!

Plus, the real time graph we watch on the computer screen is instantaneous, without the 1/2 second delay of the old system. Remember--the computer system in the 901console was designed 30 years ago, and times (and speeds) have changed. The 901 recorded data 10x per second and the new stuff records 100x per second. More measurements can be made simultaneously--two LM1 widebands, two fuel pressures (one EFI and one for carbureted engines), exhaust backpressure for two-stroke pipes or turbos, N2O bottle pressure, boost up to 100 psi, and there are 8 extra 0-5v channels that can be used as needed.

Sean and I are experimenting with dragrace acceleration tests that now can be viewed on the "real time" graph. Once we determine where the HP peak is on an engine when it takes off from a dead stop, we can program the test to mimic that--blast from low revs to peak HP RPM in a second, then gradually slide to higher revs, up chasing the climbing HP peak (as pipe center section temp climbs) for whatever number of seconds the race is expected to last.

All cold air equipment is here (four walk-in freezer condensors and evaporators) but more carpentry work/ insulation needs to be done. Typical contractor delays are forcing me to try to operate the evil and terrifying Harbor Freight $59 Chinese air nailer (trying not to crucify myself) on Labor Day weekend to ensure that we can have lots of dry winter air for EFI tuning this month. I have two EFI sleds from Utah in the bay next door waiting for cold air, and others close by, but just as anxious to miss the typical December madhouse for EFI tuning. 

2011 Apex preproduction engine data will be posted here on Sept 10, per Yamaha's request (that's when they are doing their scheduled info release). 

Wednesday, July 07, 2010

DynoTech : Summer Schedule, DYNO UPDATE

Monday, June 21, 2010

DynoTech : new dyno stuff is here, and 2011 Apex test data

My $20,000 crate of new SuperFlow 902 electronics is here now, ready to be installed on my dyno system.

Then last Friday I picked up the engine intake air cooling system from our pal Wayne Stoutner, and that will be my first project. Some of that cooling system is sitting on the dyno table visible on the engine room webcam. The cooling tunnel on the table contains four walk-in freezer evaporators that act like intercoolers, fed cold refrigerant by four 150 lb compressors. Outside air is fed through the evaporators by fans, hopefully dropping temp by 60 or more degrees F into a plenum in the dyno room. Also water vapor in the outside air will be removed by the evaporators. The idea is to feed EFI engines with controlled, dry and cold winter-like air in summer to enable us to properly tune the engines for winter operation. Tuning EFI sleds for winter operation in 75 degree F air is useless. Because of that I've recommended all EFI sled owners wait for cold air before dyno tuning--so that meant a logjam of sleds to tune as soon as winter arrived. So having winter air for tuning regardless of the weather forecast will be a dandy thing, as we should see shortly. Expect this system to be installed and operating this month.

I've got several EFI/ turbo tuners waiting for 20 degree F air, and after I accomodate them I'll proceed with the SuperFlow 901/ 902 dyno conversion which will take several weeks. I wil have a mule engine on the dyno to baseline perfectly with the current system, and then make sure we get the same accuracy with the new equipment and electronics. 

2001 Yamaha Apex

Two weeks ago Woody's Performance Center from Maine (Woody's photo appears on the homepage with his mad Methanol Supercharged Apex) brought a perproduction 2011 Apex for assessment. This session was done on Yamaha's behalf, and as such they have requested the results be posted mid August. I can say that the variable EXUP exhaust creates a huge increase in midrange torque and HP compared to running the 2011 engine without EXUP (Woody figured a way to run it both ways!).

Nearly 20 years ago General Motors Powertrain rented my dyno to assess the then-new Yamaha EXUP system on a Japanese-only 400cc four cylinder sportbike. Steve Boehm was the GM engineer who brought the bike along with high velocity strip-chart recorders to measure and record intake and exhaust pressure, and his testing with EXUP operating vs fixed open showed how valuable this then-new technolgy was for increasing midrange in the high-revving 400. Now US Yamaha sportbikes have had EXUP for years, and it's surprising that it's taken this long to apply it to the four-stroke sleds.  You Yamaha guys are going to enjoy this data.  

Sunday, May 09, 2010

DynoTech : New dyno equipment/ facility upgrades coming soon

Sunday, May 09, 2010

DynoTech : May-June schedule

5/2 Finish up YZ450 testing including one with modified head and bigger cams, stock vs GYTR vs Jardine header, big difference.

5/7 three full mod WaterX sleds tuned to max HP--ProX800 built by Tripod Sr., ProX600 built by Flannery, Rev600 built by Bill Cudney.

5/12 Heath and Mark coming with two HTG 4 bangers to set up for asphalt. Rob S will be here to tune ignition.

5/13 Jim Cooper coming for the last time, back with his original short but high HP pistons.

5/14 YammieGod Tony and a pal with a mod Yammie triple, tuning for asphalt.

5/15 Tripod's brother Minipod Mark Cross tuning mod Banshee on the shaft dyno.

5/17 Woody coming from ME with an 010 Apex Exup stocker and a big inch Nytro NA stroker/ cam/ exhaust, PCV tuning

Wednesday, April 21, 2010

DynoTech : Low HP = Successful Class Action lawsuit

Sorry guys, I'm talking lawnmowers here!

I bought a 6.5 HP Toro 22" walk-behind rotary mower several years ago. While I enjoyed the variable speed rear wheel drive, the engine pissed me off. I've been mowing lawns for over 50 years. I know what a 5 HP rotary mower engine acts like because I've used a Murray 5 HP mower for about 20 years. Since I'm getting too lazy to push a mower on my hilly one acre lawn, it was time to upgrade to a self propelled, more powerful unit. But this new 6.5 HP Tecumseh engine was all BS--bogging down where my old 5 HP Murray would have happily chawed away. It just annoyed me. And since there's no way I can dyno test a vertical output shaft engine, I couldn't verify my suspicions. I even talked to my pal Dan from Lennco in Hilton, NY about having him test my engine with his hydraulic go kart dyno which works in all positions, but never got around to doing it.

Recently I ran accross this website https://lawnmowerclass.com which proves that my assessment of the "6.5 HP" Tecumseh engine was correct. Not only was Toro BS'ing the consumer, but so were many of the other mower/ engine manufacturers. In the complaint, Tecumseh reported to CARB that this particular engine is actually less than 4 HP!

So because this one guy was even more pissed off than me and had big $ to spend on lawyers, all of us comsumers are getting refunds from the manufacturers thanks to the successful class action lawsuit! In my case, it looks like I am entitled to a refund of $35 which equals about 10% of the cost of the machine. I will apply for my $35 and report back. 

Monday, March 01, 2010

DynoTech : March/ April schedule &tc

3/3/2010 518ers Todd and Mark troubleshooting a troublesome XP800R stock hilldragger

3/4 518ers Richie and Tom tuning on their Crankshop twin piped XP800R mod racer

3/5 315er Pat Herbert dialing carbs/ timing on Crankshop Polaris 990 mod hilldrag sled

3/9 Full Power Justin dyno testing his Nytro trail mod on pump gas, plus dialing in his gonzo-injector gonzo boosted Stage 4 4tek.

3/11 greedy 518ers Todd and Tommy back again w/ CS piped XP800R testing engine changes hoping for more HP.

3/12 Dead one Dave boondocker tuning his D&D XF901 twin pipe trail mod for this weekend's HillDrags

3/12 PAer Bill Swoyer back again to fine tune Cutler carbs on his Crankshop 990 ProMod Hilldragger

3/19 Jesse Meuller, Crankshop XP800 mod HillDragger

3/23 Mike Koz, XF800 twin pipe HillDrag imp stocker, Boondocker tune to perfection (as always).

3/26 Billy Howard & Bobby Donnatelle testing the new Hindle header on the 4tek (results on DTR members pages)

3/30 home made turbo system for D&D F9 SS engine w/ boondocker turbo controller

4/8 Jim Cooper testing new longer pistons for his PS1000 SkiDoo triple asphalt sled

4/15 Casel Mulkins testing preproduction Rush 800 (results on DTR members pages)

4/17 4 Tek w/ Bondi porting and Hindle exhaust, RB3 tuning

4/21-4/23 Testing military spy drone engine, cams off

4/24 Adam Schmitt tuning revised XCR800 asphalt racer, reduced compression and lowered ports

4/27-5/2 new Yamaha 450 4stroke motocross bike, testing all available GYTR parts including CNC ported head/ cams. Testing is being done on the SF901 sled driveshaft dyno connected to the output shaft of the YZ450 trans.

Sunday, January 17, 2010

DynoTech : Jan/ Feb schedule

Thursday, January 14, 2010

DynoTech : Dyno Running!!??

Sunday, January 10, 2010

DynoTech : Dyno Down!

Monday, November 30, 2009

DynoTech : December doings

12/1 Casey Mulkins new Rush 600, then his own ported D8 with pipes and stuff:

12/2 Boyd with a Mach Z mod

12/3 Sled Shop Joe Parfitt, cams maybe off

12/4 Canadian madman James with his new F8 tuning with PCV


12/7 Shootout sleds today the Polaris Rush and D8, SkiDoo Etec and XP800, maybe a 4tek
12/8 Shootout sleds from cat- F6, F8, XFire 1000, Z1
12/9 Shootout sleds from Yamaha,

12/11 Amsnow/ DTR Adirondack Shootout in Woodgate, NY

12/13 Joe WhackPack Racing Hilldrag 800 twin mod, microphones off
12/14 Al Sled Polaris 800 twin trail mod

12/15 Rich Hoag/ John Wilbur Firecat w/ F1000 mod engine for NANO N2O tuning cancelled

12/16 Brian Babineau F7 ET900 boondocker tune

12/17 Don Pitoniak F1000 w/ pipe PCV tuning

12/18 Frank Kronkite F7 D&D900 boondocker tune

12/19 AM Nelson is bringing in big radar run cat to tune, cams off.  PM John Schwartz

12/20 AM Rich Hoag & John Wilbur rescheduled from 12/15---PM Pat Murray Sled Head 860 SkiDoo 

12/21 Polaris 4 stroke turbo tuning, big intercooler, high flow muffler

12/22 Joe Shear NY Speed lakeracer tune

12/23 Chad Bowerson PCV tune on XF1000 with D&D exhaust

12/26 Rich Hoag one more time with fixed wiring issues

12/27 NH Ross three Cats on Sunday

12/28 AM Neil Casa Dragon 800 in IQ race sled, PM Travis Beverlin

12/29 Boyesen renting the facility for private test session stock Dragon 800 and IQ600 racer

12/30 Chris Preston and pals, two Cats for tuning.

Tuesday, November 03, 2009

DynoTech : '10 sled testing, and Power Commander V

Sunday, October 04, 2009

DynoTech : October/ November dyno schedule &tc

Monday, August 03, 2009

DynoTech : August, September dyno schedule &tc

Saturday, June 20, 2009

DynoTech : "Turbo" Crankshafts, once more

Thursday, June 11, 2009

DynoTech : June, July dyno schedule &tc

Monday, May 04, 2009

DynoTech : Dyno Calibration

DYNOTECH SF901 TORQUE CALIBRATION PROCEDURE

  Our SuperFlow 901 engine dyno absorption unit has a capacity of 1,000 HP at up to 10,000 RPM. To enable us to properly test relatively small engines it’s been helpful for engine control, ease of operation, and minimizing losses from inertia of the heavy bronze absorber rotor, to reduce absorber speed by 33.33% compared to engine speed. At DTR we use a 50mm wide Gates GT2 toothed belt drive with 1.5/1 reduction. The toothed belt sprockets are mounted on 1.5” diameter steel shafts, which are supported by four synthetic greased Sealmaster NP24 1.5” pillowblock bearings.

  Like any gear reduction, this drive system converts a certain percentage of the engine power into heat from friction. This loss has been accurately measured, and compensated for in our dyno calibration process. 

  Since HP loss from friction increases exponentially as the square of engine speed, the following percentages must be added to raw calibration torque numbers to be correct at the RPM where peak horsepower occurs. These percentages were determined by dyno testing a snowmobile engine—first, direct drive to the dyno absorber (1/1) then within 30 minutes installing the (1.5/1 or 33.33% speed reduction) toothed belt drive. Engine torque/ horsepower losses at every RPM were noted. Also figured into the friction loss is a GMN470 overrunning sprag clutch that is used in the electric start system on the engine drive shaft. The following percentages must be added to the raw calibration torque to be correct at the engine’s peak HP RPM:

7500 = 7.2% added (to compensate for 6.8% HP friction loss @7500 RPM)

8000 = 7.8% added (to compensate for 7.3% HP friction loss @8000 RPM)

8500 = 8.7% added (to compensate for 8.1% HP friction loss @8500 RPM)

9000 = 9.9% added (to compensate for 9.0% HP friction loss @9000 RPM)

9500 = 11.0% added (to compensate for 10.0% HP friction loss @9500 RPM)

The SF901 torque calibration arm is 3’ from absorber shaft center to the hang point of the calibration weight. The net weight value of the arm itself is 17.5 lb. The blue steel 72 cu ft full scuba tank we’ve used for calibration since 1987 weighs exactly 40.3 lb. The raw torque value of the hanging scuba tank is 40.3 x 3’ + 17.5 = 138.4 lb/ft. That is reduced by the 33.33% belt drive speed reduction to 92.3 lb/ft. The blue 40.3 lb scuba tank should have a hanging torque value as follows to be correct at these engine speeds:

7500 = 99.0 lb/ft   

8000 = 99.5 lb/ft

8500 = 100.4 lb/ft

9000 = 101.4 lb/ft

9500 = 102.5 lb/ft

Friday, April 24, 2009

DynoTech : April, May 09 dyno schedule

Monday, March 02, 2009

DynoTech : March 09 Dyno Schedule &tc

Sunday, February 01, 2009

DynoTech : February 09 dyno schedule

Wednesday, December 24, 2008

DynoTech : Dragon 800 midrange PCIII mapping II

Sunday, December 21, 2008

DynoTech : January 2009 dyno schedule

Monday, December 15, 2008

DynoTech : One Cheater caught after the Shootout

 I have a difficult situation with the Arctic Cat Crossfire 1000 "stocker" brought in by Big Moose Arctic Cat at the 19th annual Adirondack Shootout. After reviewing the Shootout acceleration ET MPH data, I have to conclude that it was way too fast. It had to be a cheater. I am suggesting to AmSnow Sr Editor Mark Boncher who was at the Shootout, that he eliminate the results of the Crossfire 1000 from the Shootout, and leave the Z1 results as the Unlimited Class sole participant.

During the Shootout we make on-site real-time comparison of stock vs trail mod difficult since we public address and listen to 1320' results of stockers and 1000' results of aftermarket trail mod sleds. But after getting back home and assessing 1000' results of stockers I can see clearly the supposedly stock 166hp Xfire1000 was much more powerful than that. In 1000' it was as fast as D&D's 195hp 901cc piped Xfire800 clutched and driven by Scooter, and faster than Bikeman's stock Xfire 1000 with BM pipe, reeds, and dyno tuned at my place at 193hp.

I should have been diligent enough to realize that when the stock Crossfire 1000 was much faster than the Z1 in 1/4 mile something must have been amiss, and we should have teched the Crossfire 1000 immediately on-site.

Once again, mia f'ing culpa.

But even though the Unlimited Class results are tainted by this, the 600 class and 800 class results are as they should be. 

When we decided at the last minute to have an unlimited stock class to differentiate from the 800's we included the two big Arctic Cats-- Z1 turbo and the Crossfire 1000. And because it was an all-Cat class, George Taylor and I unwisely assumed that the dealer Big Moose Yam/ Arctic Cat would leave things alone and let the sleds run stock. They were already bringing a trailer-full of Cats and Yamahas to dyno certify, and a second trailer was a lot to ask. There should be no incentive for them to cheat one over one another since they were the same brand. So we allowed Big Moose to keep the sleds, no dyno certification and lock-up, let them run in the Unlimited Stock class amongst themselves. AC lobbied for some miles on the Z1 for breakin and we concurred that that was acceptable, and Big Moose was allowed to run the sled on the trail for the breakin miles AC requested with no supervision.

The Z1 was surely left stock--the timed performance was commensurate with power to weight ratio. It's reasonable to let those Z1 results be included in the Shootout.

But for now, in the interest of fairness to everyone including the very important aftermarket participants, the Crossfire 1000 results should be deleted.

After The Shootout banquet at the Trail's End Restaurant in Old Forge, Big Moose Cat tech Vince was overheard bragging that he had fooled us by cheating with modifications that I won't disclose here. That explains the too-fast performance of the Big Moose Crossfire 1000 that closely matched the 190 plus HP Crossfires brought by D&D and Bikeman.

Today I called Big Moose co-owner Phil Martin to explain this discovery. He indicated no knowledge of this cheating by Vince. I can accept that, because I'm sure that Phil and Jon Martin both have IQ's high enough to realize the negative results of this buffoonery--make the Z1 look slow so no one will want to buy them? Make the aftermarket trail mod Crossfires from D&D and Bikeman look like a poor investment? Make their Crossfire 800 sleds look slow?

I'm awaiting a response from Mark Boncher, Sr Editor of Am Snow who covered the Shootout. George Taylor and I had stressed to all dealers the need for a flawless Shootout and this is what we got. It was Mark who sold the AmSnow owners on partnering once more with us for Shootout 19, and I'm hoping this doesn't create a problem for Shootout XX.

Saturday, December 06, 2008

DynoTech : Amsnow Shootout mod sleds 12/12

Sunday, November 23, 2008

DynoTech : December dyno schedule & other stuff

Sunday, November 09, 2008

DynoTech : Kevin Cameron on breakin friction

Sunday, October 19, 2008

DynoTech : Dragon cooling improvements revised

Wednesday, October 15, 2008

DynoTech : Selling PCIIIs for Dragon 800 EFIs

Sunday, October 12, 2008

DynoTech : Dyno Over-Correction factors and agendas

Saturday, October 11, 2008

DynoTech : AmSnow/ DTR Adirondack Shootout

Monday, September 22, 2008

DynoTech : November Dyno Schedule

Monday, September 22, 2008

DynoTech : October Dyno Schedule

Wednesday, September 17, 2008

DynoTech : Carl McQuillen powers 1913 Curtiss America seaplane

Tuesday, September 02, 2008

DynoTech : September dyno schedule &tc

Friday, August 08, 2008

DynoTech : August dyno schedule etc

Sunday, August 03, 2008

DynoTech : loose spark plugs etc..

1fastxc emailed: “Hey Jim, just got done reading your article on your blog. I can definitely relate. I had
some spark plug loosening problems when i had my aerocharger on my 700 twin polaris, and didn't play
by the rules. I had a stock head on the sled and was trying to run on pump premium with about 6lbs of
boost. It would rattle the plugs loose in just a short run in the field. I figured out real fast what was going
on and knocked the compression down in the head and that took care of the problem. A friend of mine
had an interesting dilemma with some slp domes on his 800 twin polaris. SLP used to have domes for
0-3000 feet, then 3000-6000 feet and so on, with compression obviously getting higher for each elevation
change. Well for whatever reason they went to 0-6000 on their listing. My buddy ordered these domes for
his slp piped, stock motor 800 twin, which before hand ran flawlessly. After installing these domes, he
suddenly lost a cylinder while trail riding. After inspection he found his porcelain was cracked on his
spark plug. Being the very inexperienced tuner that he is, he replaced the spark plug and kept going. 
Well it kept happening, and finally he called me to ask my thoughts. Come to find out, after crunching 
some numbers for him, SLP made those domes a little to high on compression for sea level, even on the
93 octane he was running. We dropped a point or so on the compression and all was good. I've also 
experienced the porcelain breaking before on a polaris 600 e.v. with twin pipes and stock head. We changed
to a billet head with a different squish band setup and all was good. IMHO it's got to be a very high 
frequency vibration that causes this stuff. I don't know how else the porcelain would crack like that, or 
loosen the plugs that are tightened down good. To loosen plugs in the short time like a dyno run, or in 
the field like my experience, it's got to be some serious high frequency vibes. Just thought i'd share my 
experiences on the subject. Thanks for sharing these type of experiences Jim. I always love hearing about 
things like this, that way i know i'm not the only one with those type of issues.(LOL)”

----------------------------------------------------------------

Kelsey from RK Tech emailed: “I think that you are correct and pressures are not 
near 100,000 PSI internally.. More like 2500psi (normal combustion) and maybe 
4000 psi under deto (guess)..

I think there are several differences between your experiment and real 

world.

1) The "Heat" involved.. The aluminum head will expand faster (under heat) 
than the steel plug.. So, the threads in the head become larger and the plug 
is no longer held as well in the threads...

2) You also have the fact that the deto will have a direction as its 

pressure wave contacts the plug area. Meaning..it may originate from, say, 
the left side, so the plug will be hit with a "blast" that may cock the plug 
to one side and this would allow for easier movement in the expanding threads..

3) You also have oil deposits (uncombusted) that will act as a lubricant 
between the threads and the spark plug..

4) Deto also has its own frequency. So the wave will have some harmonics 
associated with it. This frequency may "ripple" the threads enough to cause 
"loosness" around the plug making it easier for the plug to "escape" upwards.

Other factors are the constant "pounding" of the deto occuring at the 

frequency of the engine and the deto freq, itself.. vs. the constant 

(non-repetative) pressure your press would yield.....

Anyway.. just some quick thoughts, off the cuff.

---------------------------------------------------------------------------------------------------------------------------

Kevin Cameron Emailed a few times: This is fascinating about the plugs loosening. Are they all .680 or .750" long reach? I will ask in aircraft engine circles to see if they are familiar with this. 

One interesting point is that at least some versions of the BMW 1500-cc 4-cylinder turbo F1 engine had a small, spring-loaded relief valve in each cylinder. That indicates that they had some bad events that needed radical measures to control them. I've seen insulators broken by deto.

I think your idea about yielding of the threads is the explanation, but with the added notion that each pressure spike causes some pretty stout sound waves to rattle back and forth many times through the metal. It might be the cumulative result rather than the single spikes. Much the same explanation as why ignition-side flywheels may slowly work their way off the crankpin in engines turning higher-than-stock rpm. The force of vibration isn't enough to push the wheel off the pin, but the general disturbance of the flywheel, being set vibrating, lets it work loose.

Some of the early castings used on testing of the engines destined for the B-29 cracked and in some cases whole pieces of the heads were broken loose so they fell out once the sheet-metal cooling air baffles were removed. They always had piston temperature problems until they adopted (only postwar) toroidal oil jet manifolds in those engines.

--------------------------------------------------------------------------------------------------------

Those guys that make the vehicle shakers, MTS, also make a device they call a "gun banger". It is used in fatigue testing gun barrels, and it applies many high pressure pulses that are very steep. I am suspecting that a lesser pressure in psi, but applied to the whole inner combustion chamber surface, would deform it enough to perhaps loosen the threads. BMW must have had some good reason to fit their race engines with those relief valves. Do you suppose they had this trouble? I suspect that only very high BMEP engines have this problem. Imagine combustion proceeding, and the flame front moves out from the central plug. Ahead of it, the unburned charge is being compressed. Because the initial density is about 2X that of a non-turbo engine, the amount of charge that auto-ignites when enough hydroxyl radical population accumulates is also large - not only because of the 2X from the presence of the turbo, but maybe also from the very high pressure pushing that end gas into squish zone and down into ring crevice spaces. When the sneeze comes, it will be a hum-dinger.

Related Q to KC from Jim C— "is hydroxyl radical (gas?) the cause of our eyes watering in the dyno engine room? I joke with sled owners here that even with all of our fine dyno instrumentation, we still stick our noses into the engine room, and when our eyes just begin to water from some noxious smell, then we know all is perfect, and there is very little extra HP to be gained with leaner mixture. Interestingly, we get that smell mostly with max HP NA and N2O engines, very little with turbos even with huge HP. Maybe turbos allow us to make our desired HP with boost and very safe A/F ratio, keeping peak chamber temps lower."

I think the gas you smell is nitrogen oxides making acid with atmospheric moisture, rather like sulfur dioxide makes sulfuric acid with moisture. The hydroxyl radicals are short-lived - I don't know if they even make it out of the engine. They are the trigger for deto, and what lead oxide (product of burning TEL) does is act as a negative rate catalyst. In our old barroom analogy, the lead oxide is the big bouncers who go up to the most excited troublemakers in the room and quietly whisper what they'll do to them if they make ANY trouble. It only works up to a certain level of excitement, after which the trouble starts no matter how many big bouncers are in the room. KC

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[537 HP is] a lot of power from one of those [1200cc two-stroke twin] air compressors. How do you make pistons last even a moment at such power? That would make a good setup for 40,000 feet, if the air wasn't too thin up there to cool the rad. That was the big problem with the B-29 - above 20,000 the air was too thin to cool it properly, so on the trips to the Empire they had to run in auto-rich to fuel-cool the engines.

Have I mentioned that the top 125s in GP racing now make a bit over 60-hp? They are singles [operating at 13,000 RPM, equal to a 1200 making nearly 600 HP normally aspirated]. Not many secrets can be left!

Also, I see that your turbo sled bmeps are very high, so I have asked if any of the air racers have had the plug-loosening experience. A wartime R-3350, operating at take-off power and rpm, sees a bmep of only 193-psi. A Merlin in air racing, making 4000-hp at 4000-rpm, is at 480-psi. Those toluene-burners in 1980s F1 were at 1000-psi for qualifying and 700-750 for the races. I guess the 125s are really four-strokes, operating in double-time. I don't know how they do it. KC

Related Q to KC from Jim—“According to Gerhard Schruf, Ferrari F1 turbo engineer during the1980’s, they ran the Formula 1 V6 turbo in testing or qualifying at 100 psi boost on 102 octane spec gasoline !!??!!”

Wednesday, July 09, 2008

DynoTech : July dyno schedule

Friday, June 06, 2008

DynoTech : June dyno schedule &tc

Thursday, May 01, 2008

DynoTech : May dyno schedule and observations

Sunday, April 06, 2008

DynoTech : April dyno schedule, tailing off now

Tuesday, April 01, 2008

DynoTech : A/F ratio comparison of Dragon 800 pipes

Wednesday, March 05, 2008

DynoTech : March Dyno Schedule

Wednesday, February 27, 2008

DynoTech : You're probably being hosed at the pump

Wednesday, February 20, 2008

DynoTech : more ETEC testing etc

Thursday, January 31, 2008

DynoTech : February 08 dyno testing

pump gas only, stock head, 139hp w/ DD monster single graph shows black stock single, blue BMP modified stock pipe, red D&D monster single pipe

Monday, December 31, 2007

DynoTech : January 2008 dyno schedule &tc

Thursday, November 22, 2007

DynoTech : December dyno schedule & other stuff

Tuesday, November 13, 2007

DynoTech : Adirondack SnowGoer DTR Shootout trail mod entrants

Tuesday, November 06, 2007

DynoTech : Adirondack Shootout Decisions for 07

Wednesday, October 31, 2007

DynoTech : Month of November Schedule etcc

Friday, October 12, 2007

DynoTech : BMP M1000 single pipe field testing by Dakota Performance

Monday, October 01, 2007

DynoTech : Dyno schedule month of Oct 07 and other drivel

Sunday, September 09, 2007

DynoTech : Kevin Cameron's new book TDC

Kevin Cameron (KC as he signs his correspondence) has written an excellent book about some of his past motorsports related experiences—a thoughtful compilation of Cycle and Cycle World TDC and other articles, plus past and current technical and social narrative.  I received my copy from Amazon.com (also available signed from CycleWorld.com) last week and enjoyed finishing it in two nights. The last time I read that lengthy a book in two nights was when, at the age of 12, I discovered a paperback copy of Lady Chatterley’s Lover in my older sister’s stuff in the attic. TDC was equally absorbing, but in a way even more enjoyable for a 58 year old with two-stroke oil sludge under his fingernails.

We DynoTechies are fortunate to have had Kevin Cameron as a friend, advisor and contributing editor for more than 15 years. In the DTR archives there are maybe 30-some TCD (The Cellar Dweller) articles that dealt with then-current issues, to help us understand the mysteries we encountered. Many archived TCD articles on our web pages are part of our current understanding of things relating to two-stroke performance. But it’s still good fun to go through them once a year for refreshment and enjoyment. New difficult-to-comprehend issues continue to arise, and KC continues to help us. When he doesn’t have an exact answer, he tries to find that answer from someplace or from someone who does. All performance snowmobilers are fortunate that KC has chosen two-stroke engines/ design/ racing to be one of his favorite fields of ongoing study, instead of Tournament Bridge.

But how was KC’s built-in encyclopedia of two-stroke ideas and theories created? And who were and are the people in his life that have helped add chapters/volumes to his encyclopedia, and even today provide ongoing sources of answers and information when we bug him for that?

Kevin Cameron is a modest person, and rarely discusses his own past—he seems to be more interested in the backgrounds of people he’s with at the time. But in TDC we get to see rare glimpses of KC as a young man in his home cellar workshop, rebuilding from the ground up perfectly O.K. new factory two-stroke racebikes, hopefully to make them better. We get to understand his relationships with people like Erv Kanemoto who did amazing things out of tiny garages to make racebikes racier and engines more powerful. And there are more, equally interesting relationships with volunteer teammates, unknown and well known motorcycle racers, many of whom began their event travels as privateers with Kevin in rusty vans with malfunctioning heating systems, and a very few of whom would ultimately wind up in million dollar Prevost motor coaches. A lot of that, and lots more technical information is in his book TDC. And very few can tell those stories like Kevin Cameron can.

Friday, August 31, 2007

DynoTech : Dyno Schedule for September

Friday, August 03, 2007

DynoTech : Lightest possible sled weight vs max possible HP

Wednesday, August 01, 2007

DynoTech : DynoJet RWHP is too optimistic

When I bought my SuperFlow Cycledyn eddy current roller bike dyno about 10 years ago, they told me to expect lower HP numbers than what I was used to on my DynoJet roller that I had just sold to a friend. SuperFlow technician Brent Williamson told me that DynoJet overestimated the mass value of their drum, leading to overstated HP. That can be easily proven by dyno testing a bike, steady state using the SuperFlow eddy current absorber and strain gauge to read torque/HP in steps, which takes the inertia on the roller and absorber out of the picture. Since a steady-state step test and acceleration only test on the SuperFlow roller dyno match so closely, we have to assume their argument is accurate.

But my argument to Brett was [at that time] there were probably 10,000 DynoJet dynos and one Superflow Cycledyne (mine would be number three). So whatever numbers DynoJet has been offering tuners and magazines are unfortunately "the standard". So I had to spend the first few years dyno tuning bikes on the Cycledyn, trying to explain why my HP numbers were "lower" than what they made on so and so's DynoJet roller dyno. The last software upgrade I got from SuperFlow a few years ago now has a "happier" "DJHP" channel so our dyno sheets can show whatever  the bike owner wants. The DJHP number is about 10% higher than Superflow's SAEHP. Good move. Sean Ray used  the new HP channel to make 138 DJHP while tuning boost and EFI fuel here on his Garrett turbocharged but otherwise stock 88 CI Softail Custom. A few weeks ago, he took it to a DynoJet dyno shootout at Stan's H-D here in Batavia and made 138 there, as well (plus runs low 11's and 120+).

Now with Justin Fuller coming to dyno his R1 turbo on my 901 shaft dyno we have more good data to compare HP at various locations on the bike. When he used my Cycledyne a few weeks ago, he made 200DJHP (182 SAEHP, SuperFlow's wheel number on the same run) at 5.5psi boost and 12.5/1 A/F ratio. And it made 195 DJHP (177 SAEHP) at a more conservative 11.5/1.

Yesterday, with my 901 engine dyno connected directly to the R1 transmission output shaft, with the same boost setting and  fuel very slightly richer (10.7/1) the bike made 189 SAE HP. That is exactly accurate, strictly torque vs RPM plus exact correction for baro, temp and humidity-- no fudging for tire slip/ drum mass estimation.

That 189 actual output shaft SAEHP, according to out two SuperFlow dynos, is reduced by 6% from chain loss and tire friction to 177 SAEHP at the rear wheel (tire). That makes sense. But there's no way the HP increases from 189 SAE HP at the output shaft sprocket to 195 at the tire (DJHP). 

So when Justin turned up the boost on his R1 to 9psi, his output shaft true SAEHP was 230, which would equal rear wheel 216 SAE HP (SuperFlow) or 239 DJHP.

I'm hoping this isn't too confusing, and is just meant to be informative. Mark Dobeck's invention and subsequent proliferation of the DynoJet roller dyno is surely worthy of a Nobel Peace Prize. 20 years ago, BDJ (Before DynoJet), there were few options for motorcycle performance people to get meaningful dyno numbers. Jerry Branch had (and still has) a SuperFlow engine dyno that connects to the rear axle of the bike. There was another one in CA that Cycle Magazine used to use that had an eddy current absorber, but not much instrumentation. Then there was my place in WNY. I was lucky to have racers like Colin Edwards' have their bikes tested/ tuned here with Kevin Cameron as consultant. Colin's team would travel here from Colorado with truckloads of TZ250's and related stuff to obtain the meaningful information they needed.

But now every bike performance aficionado surely has a DynoJet or SuperFlow (or other brand like Huff or Land and Sea) roller dyno within 30 miles to test and tune with, thanks to Mark Dobeck's vision.

Regardless of pure accuracy, any dyno can be a useful tool, if it's repeatable and you make HP progress going from A to B (or Z). Most magazines use DynoJet rear wheel numbers to publish stock bike's performance, so there's nothing wrong with comparing modded bikes with different but stock bikes on the same brand of dyno.

Just be aware that every HP is not necessarily created equally.

Wednesday, August 01, 2007

DynoTech : Just got boned buying 93 oct for an R1 turbo bike

Justin Fuller came yesterday with his R1 bike turbo kit prototype to do additional dyno tuning, and compare a different Garrett ball bearing turbo design with hopefully a bit less turbine inlet backpressure.

He had been here a few weeks ago using my rear wheel roller dyno for preliminary tuning, on 93 octane we made 195 DJWHP (DynoJetWheelHP) at 11,500 at 5.5psi boost and 11.5/1 A/F ratio. Leaning down to 12.5/1 added 5 HP to 200 DJWHP even, the number Justin was shooting for for pump gas advertising purposes. Some time during extensive road testing, Justin experienced some plug speckling (detonation) at high speed, top gear after over three miles at WOT(!!!), maybe 180mph plus?

I suggested to Justin that NA engines converted to turbochargers on pump gas are best used for acceleration in short bursts, and anyone who wants to do bonneville-style top end blasts should spend $20 for better gas to protect their $5000 engines. But Justin being a perfectionist was interested in seeing what we could get away with by switching to a Garrett ball bearing turbo with less backpressure. So he sceduled additional dyno time for yesterday.

This time we took the extra effort to dyno the R1turbo on my SF901 dyno. This required creating a custom shaft adaptor out of the R1 output shaft (please don't call it a "countershaft") sprocket. Measuring the torque and HP at the output shaft is perfectly accurate; the computerized absorber servo controls engine speed, and eliminates some guessing that accompanies drum acceleration due to mass value estimation and tire slip. With shaft connection, the dyno measures exact output shaft information, then computes engine RPM via the primary and transmission gear ratio. Also my 901 is more completely instrumented than my Cycledyn roller (that will change shortly). With the 901 engine dyno Justin could monitor fuel pressure, boost, exhaust backpressure, and get actual mechanical measurement of fuel flow with one meter measuring fuel from pump to rail, then another meter subtracting the fuel that gets bypassed back to tank. A fuel line nightmare, but very effective. The 4" air turbine measures CFM, and converts that airflow to pounds of air per hour, and A/F ratio.

Justin brought the bike just as it ran on the Cycledyn at 195djhp with 11.5/1 A/F ratio to obtain a new baseline measuring, without any loss from chain and tire. He wanted fresh pump gas to test with and I sent him around the corner to a gas station that usually sells you 93 when you try to buy it. Being a single hose multi-grade pump, the first of the three gallons of 93 that Justin bought was pumped into his truck, the next two were saved for testing (there surely is a quart or two of 87 in the mixing chamber/ pump/ hose that hits your vehicle before the good stuff gets there. Whenever you see a motorcyclist cruising around slowly looking at gas pumps before he stops at one to fill up, he's surely trying to find a pump that just delivered high test, meaning he's more likely to get 100% of whatever is in the "high octane" tank in the ground.

With two gallons of his newly bought gas and the engine well warmed up it peaked at 171 SAE HP at the output shaft peaking at only 10,300 RPM then dropping like a rock. Exerything mechanically looked good, fuel pressure, boost etc were fine.  Leaning the fuel down to 12/1 caused HP to drop even more! Remember last time we dyno'd the bike we picked up 5 DJHP by leaning to 12.5/1. 

Then Justin connected his custom deto sensor to the engine block, and he detected severe detonation just as the HP dropped on our real time HP graph on the computer screen.

Justin then enrichened his fuel flow to 10.5-10.8/1 and the subsequent dyno numbers carried HP all the way to 11.800 rpm where it made 198 SAE output shaft HP! The quiet but deadly sound of deto had subsided, and HP returned as the result of cooling combustion chamber temps with extra fuel. I was miffed that I hadn't thought of that, and Justin assured me that even with my moderate age-induced dementia I would have thought to enrichen mixture, eventually. This change was so dramatic, I need to try to post a Jpeg graph on this weblog.

So Justin sucked all of that mystery gas out of the tank, and refilled it with fresh 106 octane leaded gas. Then turning up the boost to 9psi, the engine was happy making 230 SAE output shaft HP at 10.8/1 A/F ratio, .60 lb/hphr BSFC. Justin tried leaning the fuel back down to 11.5/1 and the engine picked up enough HP to haze the clutch (stock plates w/ stiffer springs) so dyno info from that point on was useless. So those of you who might have heard Justin and I talking about 300HP, it was the engine slipping and grabbing the clutch, causing torque and HP spikes that mometarily fooled us.

Based upon Justin's RX1 and Apex sled turbo numbers, 300-400 HP is surely doable with lots of octane.

But for now, I believe Justin has had an eye-opening experience with "high test" pump gas. If he is to sell these kits for pump gas, he must tune each kit to 10.5/1 on boost. Car and Driver Magazine just reported that of something like 1500 samples of high test pump gas purchased in Michigan then tested for octane, more than 10% were low octane. Also maybe 10 years ago Dateline NBC did a private assessment of gas grade cheating by gas stations in CA, where they found one in eight substandard, with the worst testing out at 75 octane! That's too much of a gamble knowing that 8- 10% of fillups can destroy an engine tuned for max HP on high test gas, if deto sensing and protection is absent.

I complained to the Bureau of Weights and Measures about this bad gas purchase, and the director is going to that gas station, same pump, and take a sample today to be tested next week. I'll be anxious to hear the test results when they are finished.

Monday, July 30, 2007

DynoTech : Dyno schedule month of Aug 07

8/1 Justin Fuller Full Power turbo Yamaha R1 streetbike this time on the SF901 dyno with driveshaft from bike output shaft to dyno. Will compare rear wheel roller HP to actual output shaft HP. Justin wants to use 901 dyno to utilize its exact control of engine speed (no tire slip) and more complete instrumentation.

8/3 Thursday AM Jim Cooper's PS1000 still trying to cure solid mount stroker fuel flow issues. Also a PS800 Jim is setting up MSD timing for a customer of his. PM maybe Rich Daly's PS1000 on my dyno. Jim Cooper came this time with EFI fuel pump and adjustable bypass regulator--that fixed Steve Bennett's vibrating CS1710 so maybe would fix the ps1000 stroker? No luck; running as high as 9 psi we were still plagued by violent surges in fuel flow even with float bowl flooding over. Hard to rubber mount the big triple in the MXZ chassis, so possibly a rebalance of the bottom end is necessary. The PS800 Doo triple was dandy, stock crank and stock rubber mounts as we expected perfect fuel flow, Jim optimized a timing curve on the MSD, wound up with 209 or thereabouts with very broad HP curve.

8/10-8/15 Fri-Wednesday, private pro engine testing, webcams turned off.

8/15 Wed 5pm Jim Cooper back again, still same stroker crank/ solid engine mounts, this time has CNC machined upper and lower brackets to connect three megatrons into a rack.  Also Jim has  a pile of lead stick-on mag wheel weights if we need more help to calm the carbs down.  I just read Kevin Cameron's new book TDC. In his chapter about Gordon Jennings  Kevin describes how Gordon added stick-on wheel weights to a  vibrating roadrace bike to pre vent top end starvation. Hoping the same will work for Jim Coooper.   If we cure Jim's carb vibes early enough we will  tune upon  Elite Motorsports  Jack G's ps800 that made 209 last time, now with custom built Dynoport pipes. Hoping for more and/ or broader HP. Jim Cooper's fuel flow was still horrible even with racked megatrons, and even with a pound of lead weight added to bells. So we tie-wrapped my now infamous 5 lb crowbar onto the racks and presto flawless fuel delivery. Rich Daly offered me $100 for the bar, I'm holding out for $150. It will be easy for Jim to add 5 pounds to his carbs by bolting weight to his new upper and lower racks. Next we dyno'd Jack Gs ps800 Skidoo and with Jim Cooper optimized timing  and new  DynoPort nicely hand fitted pipes made 226hp with a broad hp curve from 9100-9800rpm, up 18hp from the last session due to DP pipes and perfect timing. Also backpressure was spot on--making same hp from 4-8 seconds at WOT.

8/16 AM Jeff Stinson with a prostock 700 Firecat, full mod w/ high RPM Jaws pipes, also maybe with high RPM D&D pipes, Boondocker tuning. The Jaws high revving pipes made peak hp at about 9500, well over 170hp but tuners with D&D high rpm twins are reporting 10 hp gain so Jeff may be back with a better tighter head and D&D high rpm twins.

PM Bikeman Jake Jenkins with BM F1000 ported, this time with D&D twins, Boondocker tuning for grass  tuning on 50/50 93 and 110 max HP 226/ 150 lb/ft right at the rev limiter. tuning for trail riding adding 15 lb/hr fuel on top end with boondocker = 218hp at 7500-7600 over .60 lb/hphr.

8/21 Tuesday AM Jason Price w/ F1000/1200 with big fuel pump, Boondocker N2O system, looking for 300 plus (maybe 350?) for drag racing. Jason had D&D create this F1000/1200 fitted to a Firecat chassis as a sort of clone to Glenn Hall/ Jason Stoviac's D&D twin pipe F1200 nitrous burner tested here recently.
On motor only Jason's F1200 made 221 HP at dandy fat .60 plus even with low compression and stock timing (Jake's F1000 shown above had 6 degree offset key).

Using Glenn Hall's recommended aftermarket EFI pump and high fuel pressure and his Boondocker map, we easily made 330 HP  at too safe BSFC.  Bumping  n2o to larger nozzles we were up to 356  HP .64 at hp peak, but we had a lean midrange spot .52 at 7800 that needed to be boondockered before we added any more n2o.

So after assessing Boondocker midrange I mumbled to Jason that he take his 7800 rpm Boondocker settings of 12 12 12 and add 5 to each to 17 17 17. Jason misinterpreted my suggestion to mean "change 7800 setting to 5 5 5" which would prove to be destructively lean. Goof one since I did not follow up on Jason's Boondocker tuneup..

Goof two was not listening to Jason's pal Kevin who suggested one more dyno run to ensure midrange fuel was safe and fat before stepping up N2O one more time...After having dyno calibrated more than a hundred Boondocker sleds, I was certain that going from 12 to 17 at 7800 would flatten our midrange fuel curve to perfection. Let's save Jason 10 minutes of dyno time, I know 17 is perfect, lets just increase N2O and make another step in HP...But our midrange at 7800 was down to 5 maybe like the space shuttle with a missing tile....

Either way, Jason can step back and tune to 355 with new drummed race gas (Sunoco Supreme or Maximal are my gonzo BMEP favorites), and his performance will be safe and very powerful.   And from now on he will maintain his fuel freshness with Nitrogen gas head pressure to maintain the presence of his most important "light ends" in the fuel.. When it comes to buying "fresh" just opened race gas for your $30K sled Trust no one.

8/22 I've thought a lot about our n2o deto. Goof  three was  not remembering my own winter experience with C16. I was in Forrest Lake MN, Kip Campbell had a brand new sealed drum of C16 in his garage, cold from winter storage. We went to a lake, all sleds were filled with fresh C16, all cold turbo sleds refused to start. Someone suggested a squirt of pump gas in the intake of each sled, all sleds fired up. Once they were good and warm, the C16 ran fine. Turbos make hot intake charge-- it takes lots of heat to vaporize C16. So here we are with Jason's n2o 1200, blowing huge clouds of 120 below zero n2o vapor into the streams of C16 spewing out of the nearly wide open injectors! How can that [possibly old] C16 vaporize 100% in that mostly subzero atmosphere? Goof four was loading the engine at 7000 before beginning the acceleration test at 450 rpm/sec. The engine gets the same flow of n2o at 7000 and 8500. That means that at 7000 there may be 20% more n2o ingested per revolution than at 8500. And 20% more time for detonation [deto is time dependent] to create havoc, especially if net mixture is lean and hot. Gonzo n2o engines should be loaded a few hundred revs below hp peak--we enjoy observing the massive low end hp from the n2o but it takes too many dangerous seconds to record that info. Goof five was not immediately seeing that on our final real time graph the hp was below the prior (less n2o) dyno run that was left purposely on the screen. More n2o and less hp means shut the engine down now, and it took me over one second to notice hp was low before damage occurred. With detonating n2o engines we have maybe 1/4 second of hp curve dropping below prior run before plug/ piston damage occurs. I was late pulling out. That was a two-piston snooze. I spoke to Jason today, pistons wrecked but thankfully chrome cylinders are fine, so he'll be up and going as soon as he gets pistons from D&D tomorrow. He has what appears to be an excellent tuneup at 350 hp+ (the second to last run before deto stopped our session). He also has Sunoco Supreme or Maximal race gas coming in a fresh sealed drum, which will be pressurized with nitrogen for storage.

We didn't make it to 400 as I think he hoped, but he still has 80hp more than the F10 n2o engine he tuned here before going 8.8 in the 1/4 mile. Glenn Hall's n2o record still stands, just barely.

Monday, July 09, 2007

DynoTech : Dyno Schedule month of July

Friday, July 06, 2007

DynoTech : DANGER! NITROUS VALVE RECALL

		Here's a letter sent out to Boondocker N2O system dealers. This relates to defective blowoff valves manufactured by Rehvac. Since they may manufacture valves for other N2O kit builders, everyone should examine their cylinders/ valves to make sure they aren't from the defective lot.

To:  Boondocker Dealers, Distributors, and Customers
Subject:  NITROUS SAFETY ISSUE!			
Date:  June 29, 2007

SAFETY ALERT!!

Dear Boondocker Dealers and Customers,

You will soon be notified of a safety recall by Rehvac Manufacturing that a
ffects some Boondocker nitrous oxide cylinder assemblies.  Rehvac makes saf
ety blow-off valves used on several brands of nitrous cylinder assemblies.
 This blow-off valve has a defect which seriously compromises the safety of
 the nitrous cylinder.  Because of this dangerous Rehvac defect, please obs
erve the following instructions:

IMMEDIATELY, STOP USING YOUR BOONDOCKER NITROUS OXIDE CYLINDERS and check t
he serial number of the VALVE.  If you have a Boondocker cylinder with a si
x-digit S/N number on the VALVE greater than 132349, do not use or refill t
his cylinder.  IMMEDIATELY, EMPTY THE NITROUS GAS in a well-ventilated area
, such as outdoors, using proper safety procedures.  DO NOT ATTEMPT TO USE
AFFECTED CYLINDERS BECAUSE THEY MAY BURST UNEXPECTEDLY, CAUSING INJURY OR D
EATH!

You will be notified soon regarding further details of this recall, includi
ng how the defect will be corrected.  

If you know of others who use Boondocker nitrous products and who haven
t received this notice, please tell them to contact Boondocker toll-f
ree at 1-877-522-7805.  We must know how to contact them with recall inform
ation.  

Current products being shipped from Boondocker do not have this defect.  Th
e corrected blow-off valve has a “K” stamped on the head al
ong with the burst pressure rating of “3000”.

For questions, please see the Q&A section section below. It contains all th
e information we have at this time.

Thank you for your cooperation,

Boondocker
1589 Hollipark Dr.
Idaho Falls, ID 83401
1-877-522-7805 (toll-free)
Fax:  208-524-7381
info@boondockers.com
http://www.boondockers.com 
 

Q & A for cylinders affected by this recall:

Q:  Can I use my cylinder?  
A:  No.

Q:  Can I leave my cylinder full of nitrous?  
A:  No.

Q:  Can I leave my cylinder mounted?  
A:  Yes, but the cylinder must be empty.  Using proper safety procedures, c
rack the hose fitting and open the valve to empty the nitrous in a well ven
tilated area, such as outdoors.  Remember that the gas and cylinder will ge
t cold enough to cause injury, and that breathing the gas is harmful.

Q:  How long before I can use my cylinder again?  
A:  Boondocker is working with Rehvac to quickly implement a safe plan to r
emedy Rehvac’s manufacturing defect.  For your safety, Boondocker has chosen to notify you now before all details are known.

Q:  Where do I find my valve serial number? 
A:  The six-digit S/N number is stamped on the blow-off valve body, which i
s near the knob.

Q:  What is the safety hazard caused by this defect?  
A:  The risk of a cylinder bursting is increased because the Rehvac manufac
turing defect causes the safety blow-off valve to not release at the design
ed pressure.  A burst cylinder can result in property damage, injury, or de
ath.

Q:  I am a dealer.  Should I notify my customers?  
A:  Yes, please forward this notice to them.

Q:  I know somebody else with a Boondocker nitrous cylinder.  Should I info
rm them?  
A:  Yes, please forward this notice to them.

Saturday, June 16, 2007

DynoTech : Discussion w/ Kevin Cameron on torsional vibration

I emailed to Kevin Cameron today:

Kevin

Last week I if you saw my blog I had an awful vibrating solid-mounted 1710cc crankshop triple asphalt sled brought here because of fuel flow issues (shutting off at half-track). From 6500-8000 the carbs were a blur, 90 lb/hr fuel flow was all we could muster couldnt support 300hp for more than 4 seconds. I bought a piece of aluminum strap and bolted it to the tops of all 3 flatslide carbs to tie them together hoping to settle them down. That actually made fuel flow worse. After maybe fifteen seconds of run time, the surface of the smooth aluminum bar and carb tops were fretted where they contacted each other.

Is that fretting localized melting/ transferring of metal from bar to carb? That would mean the small contact surfaces are reaching 1200 deg F from friction.

We switched to a brand new smoother running 1710 engine (turns out the first engine's crank was out of phase), added some rubber to the motor mounts, and fuel flow was good with just the right fuel pressure

Also Ive had a question posed to me by a guy on the internet about changes in torsional vibrations in the wicked turbo boosted big bore F1000 twin with about triple the stock torque output (and 414hp instead of 165 stock that I just posted on DTR), but operating at stock RPM. This guy has a boosted Yamaha RX1 or apex, and he's galling clutch parts, so he's suspecting that the same would happen to the Arctic Cat big twin. The twins are a little buzzy stock, and 280 lb/ft is maybe not constant, probably rising and falling twice/ revolution? could it be 400 lb/ft relaxing to 100 lb/ft twice/ rev (somehow averaging out to 280)? If I use a solid non rubber shaft from the engine to the absorber, there's a way of using an oscilloscope to observe/ measure the torque spikes each revolution. I did that  once after I built the dyno  20 years ago to ensure that my lord soft rubber couplers were doing their job, and the oscilloscope was nearly a flat line.I should do that again with a solid shaft with stock, turbo, and N2O added to see what the crankshaft is putting up with. I could also do that with a Yamaha 4 cyl, which has some rubber in the output shaft gear I think, which probably gets wound very tightly  under  boost.

Just looking to clarify these things.

Thanks
 Jim C.

also here's the Hardcore Sledder internet post I was referring to:

Super Advanced Member Current Sled: 2005 135.8 MPH Mach-Z Previous or Other Sleds you Own: 03.5 blair morgan, Location: Eastern Ontario Favorite Riding Area: eastern Ontario Mileage so far this winter: 00000000 Mileage last winter: 607 Your Age: 41 Riding Since: 75 Group: Members Posts: 157 Joined: 6-February 04 Member No.: 9,778	QUOTE(DynoTechJim @ Jun 14 2007, 05:20 PM) < motorsport17 is teasing because he knows I have bulletproof glass in front of my face looking out into the dyno room, but 5/8" drywall in front of my testicles. That's why Glenn, Jason and Dale were fighting to get that seat right behind me in the control room to use my body for a shrapnel shield. Also galling clutch parts are in my opinion due to torsional vibes not pure torque. Jim Just a question fo you I would have thought that a 2 stroke 1000 would have more torsional vibration then a 4 stroke yamaha. Please correct me if i'm wrong Thanks Cliff -------------------- making them fast one sled at a time!
top	quote this post

DynoTechJim

Yesterday, 03:04 PM Post #28

Member Group: HCS Advertisers Posts: 16 Joined: 31-January 07 Member No.: 40,320

Cliff that is more of a Q for Kevin Cameron than me. Surely the stock F1000 crank is smooth enough at operating speed from say 6500 to 7800, but they surely have some evil vibrations between idle and clutch engagement where you dont spend much time at. Glenn has nearly triple the stock torque of the engine, so I bet there are worse torsional vibrations with his monster turbo than stock due to the increased torque peaks two times per revolution, winding up and unloading the crank, maybe 50% harder, twice each revolution even though he's operating at stock RPM. My only first hand experience with aggravating torsional vibes in a 4 cyl 4stroke was my old Suzuki GS1100 that I big blocked to 1394cc plus larger cams. once modded this thing was loaded with torsional vibrations. Though I couldnt feel anything while riding, the vibes were evil enough to continually snap the socket head cap screws that attached the inner race of starter sprag clutch to the flywheel on the left side of the crank. The inner sprag race is a light thing, probably incapable if having enough inertia to snap bolts regardless of the severety of the vibration. So what I think was happening was at some RPM, dont know where, the flywheel was actually going backwards for an instant, driving the starter ring gear into the starter drive gear like an impact gun, eventually shearing the bolts. I think this happened twice, then someone sold me a set of grade 10 bolts or something like that that all big bore modded Suzukis required. Problem solved, but surely the life of the sprag clutch/ gears would have been short had I put many miles on it. But I had done four things to create the evilness in the crank--heavier pistons, way more torque, higher revs, and straight cut gears between crank and countershaft plus a clutch basket nearly devoid of the soft springs that normally soak up vibrations from the right side of the crank (the starter drive and flywheel are of the left). I don't know which aggravated that Suzuki crank the most, maybe it was a combo of all four. But you have to appreciate how bad the vibrations were when you think about the crank end actually going backwards for an instant one or more times per revolution at some RPM between 1000 and 10,000 (maybe at several different RPM). Kevin Cameron has addressed this in the archives on my website, and he may be able to elaborate on pure torque increase and effects on torsional vibrations. That's another issue I will raise the next time I talk to him. But if Glenn eats up his 6-weight clutches I suspect it will be from mostly from increased torsional vibration, not just the added twisting force.

Tuesday, June 05, 2007

DynoTech : Month of June 07 schedule

Wednesday, May 09, 2007

DynoTech : UPDATING DYNO ABSORBER 5/21

Tuesday, May 01, 2007

DynoTech : month of May 5/30

Thursday, April 05, 2007

DynoTech : Month of April

Friday, March 02, 2007

DynoTech : Month of March

Monday, February 05, 2007

DynoTech : bathtub cylinder heads vs shrinkwrapped cylinder heads

Tuesday, January 30, 2007

DynoTech : Month of February

Wednesday, January 03, 2007

DynoTech : Month of January

Sunday, December 24, 2006

DynoTech : subscribers who can dial in chassis' for others

Friday, December 01, 2006

DynoTech : Month of December

Tuesday, October 17, 2006

DynoTech : Month of November

Wednesday, October 04, 2006

DynoTech : Month of October

Friday, September 01, 2006

DynoTech : Month of September

Saturday, August 19, 2006

DynoTech : Hardcoresledder-no more for me

Sunday, August 06, 2006

DynoTech : Month of August

Monday, July 17, 2006

DynoTech : Month of July

Monday, June 05, 2006

DynoTech : Month of June updated

Saturday, May 06, 2006

DynoTech : Month of May updated

Friday, April 28, 2006

DynoTech : Stock sleds needed for drive belt testing

Saturday, April 08, 2006

DynoTech : Week of 4/9/06 and beyond

Monday, March 27, 2006

DynoTech : week of 3/26

Wednesday, March 22, 2006

DynoTech : week of 3/19

Sunday, March 05, 2006

DynoTech : weeks of 3/5 and 3/12

Sunday, February 19, 2006

DynoTech : weeks of 2/19 and 2/26

Friday, February 03, 2006

DynoTech : weeks of 2/5 and 2/12

Saturday, January 21, 2006

DynoTech : Weeks of 1/22 and 1/29

Sunday, January 15, 2006

DynoTech : Week of 1/16

Saturday, January 07, 2006

DynoTech : Friday 1/6 forward

Saturday, December 31, 2005

DynoTech : This week's Dyno schedule update

Thursday, December 29, 2005

DynoTech : Dyno update

Tuesday, December 27, 2005

DynoTech : Rest of dyno schedule

Tuesday, December 27, 2005

DynoTech : Finally figured out my blog password

Sunday, December 18, 2005

DynoTech : Sunday's Dyno tuning results

Saturday, December 17, 2005

DynoTech : Saturday's dyno tuning results

Friday, December 16, 2005

DynoTech : Some new data

Friday, December 16, 2005

DynoTech : This week and Boss Noss tuning

Sunday, December 11, 2005

DynoTech : Seven days a week-- Sunday's results

Saturday, December 10, 2005

DynoTech : Back from Shootout

Wednesday, December 07, 2005

DynoTech : Wednesday before Shootout

Tuesday, December 06, 2005

DynoTech : this dyno session ZR800 Boss Noss

Monday, December 05, 2005

DynoTech : Shootout certification update--

Saturday, December 03, 2005

DynoTech : Final shootout dyno certification

Thursday, December 01, 2005

DynoTech : more shootout news

Tuesday, November 29, 2005

DynoTech : another Shootout update

Saturday, November 26, 2005

DynoTech : Dyno Schedule

Monday, November 21, 2005

DynoTech : The rush is on

Monday, November 14, 2005

DynoTech : This week

Sunday, November 13, 2005

DynoTech : communicating with scandanavia

Thursday, November 10, 2005

DynoTech : F6 followup, next week's agenda

Wednesday, November 09, 2005

DynoTech : Sean Ray dyno tuning F6

Monday, November 07, 2005

DynoTech : another F7 150hp stocker

Saturday, November 05, 2005

DynoTech : Saturday results, thumbnail sketch

Friday, November 04, 2005

DynoTech : Saturday/ Monday dyno sessions

Tuesday, November 01, 2005

DynoTech : Sean Ray dyno tuning tonight

Friday, October 28, 2005

DynoTech : upcoming dyno stuff

Friday, October 21, 2005

DynoTech : D&D/ Glenn Hall test session

Thursday, October 13, 2005

DynoTech : Bikeman F7 test session

Tuesday, October 11, 2005

DynoTech : Just finshed session with Excell Motorsports

Monday, October 10, 2005

DynoTech : Disabling dyno room houseflies w/ Surefire Mapp Gas Torch

Wednesday, October 05, 2005

DynoTech : Cool weather is finally coming,,,

Monday, September 26, 2005

DynoTech : Cameras shut off for a week

Wednesday, September 14, 2005

DynoTech : Dynotuning F7 and Fusion 600 tomorrow

Saturday, August 27, 2005

DynoTech : More dyno maintenance and DTR/SW update

Wednesday, August 24, 2005

DynoTech : Tuning today

Friday, August 19, 2005

DynoTech : F7 carbed update

Tuesday, August 16, 2005

DynoTech : new DTR HP record

Sunday, August 14, 2005

DynoTech : Brute HP shootout

Friday, August 12, 2005

DynoTech : DynoUpdate

Thursday, July 21, 2005

DynoTech : Finalizing sled dyno overhaul

Tuesday, June 28, 2005

DynoTech : Summer happenings---

Thursday, May 12, 2005

DynoTech : more updates.......

Tuesday, April 19, 2005

DynoTech : Latest dyno cam schedule (slow season is here)

3/6/05 9am Dan Cross HTG 800 Storm Trail Mod

3/6/05 5pm Nascar's Buddy Parrot's 113ci H-D Softail turbo, Sean Ray tuning for 200hp. 3/23/05 Cooper's Sales & Service 05 SkiDoo 440 snoX sled w/ 800rev engine, baseline stock today then pull cylinders, have trailporting done 3/24 then redyno Friday 3/25
3/24/05 5:00pm CycleDyn Sean Ray supertuning Al Specter's 113 S&S Aerocharged bagger.
3/25/05 Finishing up Jim Cooper's SkiDoo, hoping that trail porting will get him 150 HP+ on pump gas.
3/25/05  afternoon, 3/26/05 afternoon, CycleDyn tuning  2 Yamaha flat track race bikes- one 80cc 2stroke,  one 450cc 4stroke.
4/2/05 AM final dyno assessment of Blue Marble oil on Jim's XLT600 baseline dyno tested with Polaris oil, six dyno runs repeated within a few percent, then drained and switched to Blue Marble, trated cylinders twice per instructions, 100 miles on trail with Blue Marble, back to redyno in 4/2 AM.
4/6/05 Kevin Dellinger two Cat triple asphalt sleds
4/8/05 Dusty U's D&D F9 stroker with twin pipes and with new Giant Single and stock muffler, then in PM D&D's Dale Roes with a new F9 stock stroke, Giant Single stock muffler.
4/22/05 Fri 11:00AM Bill Looneytoon DiFranco dyno tuning his asphalt sled Boondocker box. I predict we will find him 3/10ths in the 1/8th mile.

4/27/05 Wed 9:00 AM Kim Peckler, HTG XCR600/800 (while her husband Tom E4 watches his sled being dyno'd live on the internet in Baghdad Iraq).

4/29/05 Fri 9:00 AM Scott Trapp dialing in his carbed F8 for asphalt.

Friday, April 01, 2005

DynoTech : Things we will be testing

Friday, April 01, 2005

DynoTech : update dynocam schedule

1/2  AM Tom Reynolds mod Viper [trail ported by Tom, bored carbs, pump gas, Hauck trail pipes 160 HP]
1/3 AM Dan Johnston 03 F7 [107 lb/hr stock, then he used his own $20 needle valve to choke down to 100 lb/hr and 145 HP]
1/4 Steve Orlaski 03 F7 10 AM
1/5 Jim Gonyea, FastEd and one other Italian lakes madman, two F7 EFI's one carbed
1/6 AM Rich Simonetti F7 of some sort
1/7 Paul Coleman 04 F7 am, Gary Claxston 04 F7 EFI, pm
1/9 Adam Bonner 04 F7 10 AM, Larry Bartlett 12pm 04 F7, maybe later a F5
1/12 Dan Roes- D&D Performance, bone stock 05 F7 then with new D&D twins. See it live on DTR webcam beginning at 10 AM. Also F8 top end w/ monster twins into STOCK MUFFLER [=stock dB].
1/12 HTG Racing, Fusion Big Bore with DP single pipe and/ or can [cancelled until production stamping of single pipe is available].
1/14 9AM, Robert Morris Bikeman F8 with D&D new monster twin pipes [some problems]. Then Patrick Ferland, Quebec EFI F8 12 PM or deux heurs [CANCELLED]..
1/15 9am Dave Craiglow, DD F8 twin pipe/ Boondocker EFI controller, Bill Looneytune DiFranco assisting. 1PM, two 1132 Cat D&D triple lakeracers, Dave & Jeff want to be anonymous.
1/17 9AM AJ Andre, ProX800 lakeracer mod, twin pipes and with Boondocker N2O system [CANCELLED] AJ is a snowplower in NJ, and there is snow on 1/17.

1/19 D&D F8 w/ stock can twin pipes[CANCELLED] Dan has flu, [no flu germs allowed here]

1/21  9am Curt Allen [cancelled, waiting for D&D twins into stock muffler!]
12pm Tom Tyson, HTG 1080 pump gas triple, new Jaws pipes
1/22 2pm Patrick Ferland F8, dialin Boondocker EFI box
1/23 9AM D&D F9 !!!
possible problem with dyno electric starter sprag clutch, cancelled all dynos until fixed...
2/1/05 New GMN $480 sprag clutch installed, back to tuning
2/2/05 Bill Mead Bikeman F8, tuning Boondocker EFI box
2/4/05 AM, Jimmy Tanner, F7 dragracer tuning 500' and 1000' setups
2/4/05 PM Jarred F8 DD, tuning Boondocker box
2/7/05 AM Jim Gonyea and pals, Hooper 1400 triple [cancelled]
2/9/05 AM two Cat mods- 700cc & 1000cc
2/10/05 AM Jim Gonyea and pals, Hooper 1400 triple
2/11/05 AM F7 stocker w/ Boondocker box [cancelled]
2/22/05 Les Ferenczy F7 stocker, DTR style Boondocker box, Bikeman mod stock pipe [CANCELLED]
2/25/05 Jeff Sherlock, two troublesome ZR800 big bores to analyze
2/26/05 2pm Matt Bennett new D&D F7 757 big bore, maybe w/ new Boondocker if needed [boondocker was not needed]
3/2/05 9:00 AM DNE Perf, Don Emery (1) Mach Z twin w/ porting etc plus Bikeman stock pipe mod, (2) 1234cc 4 cyl radar run engine, made 280 HP here last year, shooting for 300,  (3)  Gonzo larger bore 4 cylinder radar engine, shooting for  Bender's 359 HP DynoTechResearch HP record and 172 mph Ontario radar run record.
3/3/05 9:00 AM Mike Gross ProX800 trail port, SLP trail port single pipe, pump gas heads and race gas heads.