Originally Posted by Coheed 
So there is some new results out. TS tubular manifold .78ar divided housing, vs a log manifold .63 housing. Both graphs are 24psi, 3rd gear pulls. All I did to make more power was put my timing back to where it was last year!
I backed timing off by about 4-5* in order to have a more conservative tune. Well, let's just say the car loves timing.This is twin scroll vs single. I switched intake cam sooner at 5200rpm instead of 6500rpm, that is the why the powerband is a lot better.
Here is a 3rd gear vs 4th gear. 4th made more power! Great to see the clutch actually holds 4th now! :biggthumpup:
So even though I didn't make a ton more power than before, it does spool faster slightly, and the transient response is killer!
I must say the extra timing really woke the car up. I went from 380whp to 440whp with just 4* of timing. The guys wanted me to keep going because they couldn't hear any detonation or anything, but i didn't want to push it lol. I am happy to see that the power is back where it was with no compromises. AFRs are amazing too. How's that for a JWT tune!
Ok your car reacted that dramatically to 4* of timming. Not suprising really, BUT JUST IMAGINE WHAT A FULLY TUNABLE ECU WOULD DO!
Originally Posted by Coheed I wish I could log the boost. Hits 15psi easy at 3700-3800rpm, it just doesn't start charging hard until about 5000rpm still. I guess the Volumetric efficiency isn't in a sweet spot till then.
With more timing it would respond harder. I put the timing at exactly 15*, turns out when I dyno'd last week my timing was around 11* because I set the dizzy straight up. When I machined the head down a bit it retarded my timing a bit more than I thought. Either that or the crank gear timing mark is off a bit. But the motor really reacts harder to the more timing.
I did try switching the exhaust cam at 6800rpm, but it didn't seem to make any more power. The exhaust is still too choked up to get any better flow with the bigger duration. The VE cams still won't make good power with this turbine housing though. As the boost got turned up they didn't like it.
I think a 1.06 T4 housing would make power like a .63-.82 but spool even faster than this .78. The .78 moves air at low rpms, but the motor still seems choked up somewhere. The .78 does spool faster, but I have a feeling that either the cams or the housing is already a restriction past 7K. I needz mo flow!
once again this would be due to your tune! most mail order tunes have very conservative timing figures around 3000-5000rpm. if you are making the psi and not the power it is most likely your tune! get something that can FULLY tune your set up, whether it be a tunable remap or full standalone. You car WILL be much faster, spool harder and be a better car to drive all round.
I knew it wasn't your housing that was the core problem. You can not deny the difference a proper tune will make if 4* of dodgy ass dissy timing gives you 60whp!!!!! Think of the power band a tune will give you.
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. So I don't think it will react very hard until a much larger housing goes on. I still think the stock cams are going to lose power because there is simply too much backpressure still.
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