Power Versus Boost

[blueboost]

your power should peak where you drop down to 13.5psi so that why it only made 290, even though it got back up to14.5psi it will not recover, fix the boost line up and she would make 320rwks, which if it is a BA 4speed auto, your power will not be far off the mark

most 12psi cars go like 12psi cars even if they think they have 380kws or not. ( there is a bit for efficient intercoolers and turbo's though too)

so I would be asking why it drops off to 13.5 psi at peak power if I was you.

David

Edited 19/07/09 06:03 AM by blueboost

[ugy]

Forgot to mention. The wastegate has been ported and 12psi actuator and it is an auto Also pointing me in the right direction why would the boost drop like that?

[blueboost]

it needs to be tuned

[Adam]

David, isn't it also to do with the tuning itself?

From what I understand similar power can be achieved on higher boost with less timing and lower boost with more timing.

[blueboost]

yes there is more to it then I made it sound, but some figures are just unrealistic that is all ,

the main prob with his car is it does not make 15psi at peak power the best way to tune is the most timing for each boost level that is safe,

18 psi making 300 kws is not the way to do it.

David

Edited 19/07/09 06:29 AM by blueboost

[Adam]

My old BA always ran 15psi with different part configurations and from power levels ranging between 250-310rwkw's.

My current BF on the other hand makes 300rwkw's on 12psi.

[blueboost]

yeh your not comparing apples with apples, a BF makes more power, and its gearbox in auto is way more efficient, to compare you would remove 25-30kws from yours.

your car at 15psi and making 310 was right, but if it was making 250 at 15psi it was done wrong.

Edited 19/07/09 07:12 AM by Adam

[Adam]

The 250 was with stock everything except injectors and valve springs.

While peak boost was 15psi I'm sure it tappered down by the time peak power was made.

[ugy]

This is the dyno read out done by the tuner that done the wastegate mod. Since this tune and the previous dyno day sheet I had the cat removed ( Ballistic 3 inch with 5 inch body ) and replaced with a 3 inch pipe because it was hitting the floor pan. I wouldn't think the removal of the cat would make any difference as it basically flows the same as a 3 inch pipe anyway

[Boosted1]

just thought I would add, boost is a measurement of restriction. so one car making 300 on 15psi could have a standard dump and exhaust... (more restrictive to the flow of air/ exhaust) where as one with 300 on 12 psi could have aftermarket exhuast cooler dump etc which is less restrictive. (just exaples)

with my old car (supercharged v6 commodore) this was alot more crucial than the turbos are

hope you can understand my jumble