Wistech 470 historic

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kdeal · #11 Post by **kdeal** » Sun Feb 04, 2007 9:17 pm

Any one notice how Wistech was so worried prior to the runs that the motor would blow chunks, but when the dyno runs were done he put C27 (alias I live on the red-line) on the bike? Hey C27, I think Wistech was worried on this one......LOL

wistech · #12 Post by **wistech** » Sun Feb 04, 2007 9:59 pm

Hmm? An engine that had heat damage on the rod big end from a main bearing failure. An engine that tears flywheels up and spits them out. An engine that has enough power to snap one case in two and break another. An engine with a clear valve cover for protection from ejecting parts . An engine running on highly volatile oxygenated fuel . Heck no Im not running that thing on the dyno. I didnt bring my kevlar cup so I was happy to let Steve do the runs. I just tried to stay out of the blast zone. Even though it pulls flat all the way to redline NOBODY suggested turning up the rev limiter on this baby. I could just see the mushroom cloud when it would have detonated at 12,500. Cripes it was knocking pop cans off the computer stand on the 5th gear runs.

cannondale27 · #13 Post by **cannondale27** » Mon Feb 05, 2007 12:30 am

Hes not kidding.First time I had to steer the quad while dynoing.
Check this out.If you use time rather than RPM they all peak right about same time.500,1000 and lastyear same quad which had 500ecu and I believe all these were filter on and good flywheel.Notice how much longer the 1000 pulls time wise.Starting points need to be disregarded since as operator its almost impossible to start at same rpm everytime.I think this may be a indicator of drivability.For sure wouldnt need to shift as quick.

Same runs But RPM.

claas900 · #14 Post by **claas900** » Mon Feb 05, 2007 2:18 am

QUOTE (wistech @ Feb 4 2007, 04:26 AM) <{POST_SNAPBACK}>

I believe more and more that the afr doesnt mean squat for tuning for max power. This engine pulled the best numbers in hp and torque before we modded the map and got the line straight. Drivabilty on the other hand might be suffering but its hard to tell when they have so much power everywhere. I will take it out and run both setups to see how they perform.

A few weeks ago I was doing some research on 02 sensors. And a few ppl were saying that using afr wasn????????t the best way to tune. Its more for ball park. They were saying that it????????s become a big fad 02????????s were. That the best way to tune was egt. But all motors like different egt????????s.

wistech · #15 Post by **wistech** » Mon Feb 05, 2007 3:14 am

This brings up a few basic questions. Does a perfect flat across the board 13.5to 1 afr = max power /torque?
Is the perfect afr directly proportional to good drivabilty? I think we need to do more testing. Ill swap between both ecu's to see which one I like the feel of. This is some interesting stuff.

hawksd1 · #16 Post by **hawksd1** » Mon Feb 05, 2007 3:28 am

Hey wistech Im not super mechanic like your self but I had a thought today while reading your dyno runs...We basically have what would be considered a throttlebody injected motor well... what about direct injection through the top of the head. Is there a way to machine in an injector or would you even gain hp from direct injection. Just a question that ran through my head today...lol

wistech · #17 Post by **wistech** » Mon Feb 05, 2007 4:38 am

I think a throttle body injection is an injector above the TB plate spraying low fuel pressure. This is mimicking a carb setup. Id say ours is port fuel injection with the injectors a tad farther from the valve than we would like and they spray at higher fuel pressure . I have no clear idea on how gasoline direct injection works and if gains could be made.

Super mechanic? Id say Im average . Im no genius engineer but I have learned basic priciples on why things need to be built a certain way to get the results needed. I dont cry when I lose an engine once in a while either. Ill pick up the pieces and try to learn as much as possible from it because I know the next one will be better.

J. Delaney · #18 Post by **J. Delaney** » Mon Feb 05, 2007 6:21 am

QUOTE (wistech @ Feb 5 2007, 03:14 AM) <{POST_SNAPBACK}>

This brings up a few basic questions. Does a perfect flat across the board 13.5to 1 afr = max power /torque?
Is the perfect afr directly proportional to good drivabilty? I think we need to do more testing. Ill swap between both ecu's to see which one I like the feel of. This is some interesting stuff.

Nope. Stoich is theoretical. Tuning on a dyno is a valuable tool, but you still need to go ride the thing to tune for drivability. Theory, when put into practice, is not always perfect.

cannondale27 · #19 Post by **cannondale27** » Mon Feb 05, 2007 12:44 pm

When we dynoed this one for instance first I got as flat a AFR noted hp as possible then we moved whole line up (leaner)and noted hp and down(richer) then noted hp when we start to see it increasing we go more till it has no hp effect then go back down.All the while trying to keep afr flat.If a flat AFR isnt needed it would save a ton of time.J.Delany is right.Max hp has been achieved at varyious afr's I am sure there must be a pattern but anywhere from 12-1 all the way to 14-1.My YFZ buddies YFZ liked to be near 15-1.

kdeal · #20 Post by **kdeal** » Mon Feb 05, 2007 12:52 pm

QUOTE (wistech @ Feb 4 2007, 11:38 PM) <{POST_SNAPBACK}>

I think a throttle body injection is an injector above the TB plate spraying low fuel pressure. This is mimicking a carb setup. Id say ours is port fuel injection with the injectors a tad farther from the valve than we would like and they spray at higher fuel pressure . I have no clear idea on how gasoline direct injection works and if gains could be made.

Super mechanic? Id say Im average . Im no genius engineer but I have learned basic priciples on why things need to be built a certain way to get the results needed. I dont cry when I lose an engine once in a while either. Ill pick up the pieces and try to learn as much as possible from it because I know the next one will be better.

Wistech is right. Just because you have a throttle body does not mean TBI. The TBI system is as closed to a carb you can get as there is one or a pair of injectors in a throttle body providing fuel. Ours is definitely port injected just like most vehicles now a days. Ergo, one injector per cylinder minimum injected in the port after the throttle body. Wistech is too young to remember the birth of modern day fuel injection in vehicles...LOL. Of course you could always go back to the old 60's Corvette for FI as well..........

I believe Bosch was a pioneer in the port injection type of fuel injection. I worked at a GM parts counter when I was a wee lad and saw most of this develop years ago.