ITB's
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Originally Posted by ronac,May 26 2008, 10:56 AM
A bit off topic but I was wondering, for you itb guys, what afr are you guys tuning to for power?
I've been targeting around 13.3 but I have a feeling I could make a bit more power if I ran a bit richer.
FYI, I dyno'd my car this weekend and also had a friend with a ap1 with test pipe and K&N dyno as well. He was sort of my baseline to compare to. I'll post the plots up once I get them.
I've been targeting around 13.3 but I have a feeling I could make a bit more power if I ran a bit richer.
FYI, I dyno'd my car this weekend and also had a friend with a ap1 with test pipe and K&N dyno as well. He was sort of my baseline to compare to. I'll post the plots up once I get them.
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I was just doing some logging with the aem ems recently and used that dyno math thats found in the aem forum. I noticed 13-13.3 make pretty much the same amount of power, but as I got leaner, the power goes up quite a bit.
I think I may try to target 13.7 and see how that goes. Thanks for the info about the AFRs'.
About my itb's, they're not TWM. I built the itb's custom with Hayabusa throttle bodies.
I think I may try to target 13.7 and see how that goes. Thanks for the info about the AFRs'.
About my itb's, they're not TWM. I built the itb's custom with Hayabusa throttle bodies.
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From: Frustration
Adding a plenum is a waste of time unless you are going for a proper ram air system.
Worse still think of the turbulence you will get from having stacks inside it!
And also think that if you ran that type of plenum, you could get away with 1 butterfly instead of 4.
You are slowly returing to the original inlet manifold design.
I think you have all got distracted from the true dynamics of ITB's with a bit of CF bling
Worse still think of the turbulence you will get from having stacks inside it!
And also think that if you ran that type of plenum, you could get away with 1 butterfly instead of 4.
You are slowly returing to the original inlet manifold design.
I think you have all got distracted from the true dynamics of ITB's with a bit of CF bling
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From: never never land
Originally Posted by s2kennmark,May 21 2008, 02:22 AM
if you can figure out a plenum that will contain your horns and still deliver good volume inside then go for it.... really hard to do it on s2k due to little space.
francesco, you mean you wanna see ITB in general with plenum? go look at E36 M3s.
francesco, you mean you wanna see ITB in general with plenum? go look at E36 M3s.
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From: F L O R I D A
I was looking at a Euro Datsun forum site where someone made a plenum for there ITBs. Its based off the old audi rally cars I believe and were able to recreate it for his car and actually was able to get even air flow to each runner.. Also they were boosted.
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From: F L O R I D A
Heres the site. Kinda long but real informative. Maybe help gives us some ideas to make one.
http://forums.hybridz.org/showthread...=127863&page=7
http://forums.hybridz.org/showthread...=127863&page=7
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From: Frustration
Originally Posted by ITBs2k,May 31 2008, 11:48 PM
Also they were boosted.
And if you look at the thread the CFD diagrams don't include the cylinders and are calculated on all intake ports being open at once (not the case obviously).
Intake flow is a lot less important with boost, than it is with N/A (thats not to say it isn't important with boost BTW!)