very very interesting everybody! I'm open to all this, and will definitely be proving/disproving whether or not an open airbox or fully closed stock airbox w/ snorkels installed will work best on MY particular motor at a dyno appointment I have two weeks from tomorrow.

You know, some of us ask ourselves - If all this is valid, then why would removing the lid cause the mixture to lean? I mean it does lean, we all know that, and we all have always assumed it leaned due to more air flow, but perhaps it leans merely due to loss of vacuum acting on the main jet, thereby sucking less fuel up and needing a larger jet to make it easier. Put the lid back on, increase the air flow through all the proposed principles here, and suck more fuel from a given jet size, and jet down as a result.....sounds logical....we'll see in a couples weeks, unless Mr. Horsepower beats me to it (I hope he does, Dyno time is expensive for me!)!!

 

I agree with hightower, this is interesting! I'm glad to hear there will be one more person doing some fine tuning on a dyno. We all know comparing results from even a slightly different dyno can be useless, however by tuning a single bike till you get peak hp on that dyno in that session, I think that is golden. It's not 100%, however if Hightower sees certain benefits from changes he made that show up on the dyno, those changes will be relevent for everyone else. I'm starting to think that dyno testing is the only 'true' test and that seat of the pants is really a waste of time.

Since I don't have a dyno, I think I'm going to test on some changes as recomended by Eric on my machine this weekend using the only concrete test I have - the stop watch. It's not nearly good as a dyno, however it is at least consistent. (As long as the person hitting the buttons is accurate!)

 

Details, I can't help it. 95sport400, that would be 137 suction pulses per second TOTAL on your example above. It's a four stroke, right. One pulse per cylinder every TWO revolutions of the engine. I guess you didn't leave all the two stroke stuff out......LOL

 

As I said, that's not me - it's from SnowmobileWorld.com. They're primarily looking at 2-strokes but they mention V-8's and superbikes so one could assume the same principals applies to all.

Remember, "Don't shoot the messenger"!

p.s. - it's 3:20 AM and I just got home from the bar. As much fun as my quad is, chicks are still more fun!

 

Farmers!!! man they sure do love their jobs[img]i/expressions/face-icon-small-happy.gif[/img] LOL

 

ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ

 

After reading this i went out too firebird last night walked straight out to mickey iva. (i belive i might have interfeared with his burn out !!!) and kicked him in his AZZ !!! Him and that dang !! gram pa pa Iva had been telling me all wrong for years so i ripped his velocity stacks off his bike and slaped a stock air box on that bugger!! and i belive firebird speedway seen its slowest run ever last night during a practice session!! well now im not allowed out at firebird Raceway (with out an escort) any more so thanls for the info GUY's!! dang drag racers i showed them[img]i/expressions/face-icon-small-happy.gif[/img]


PS:A little disclaimer here this in noway was meant to offend any of the Iva's or the sneavas'or the garletts the true racing legends!!!

 

I didn't know Mickey Iva started racing a DS [img]i/expressions/face-icon-small-wink.gif[/img]