30th t/a

iTrader: (51)

i thought 20-25rwhp per 1lb of boost.

most bone stock Ls1's are roughly 300rwhp stock. so i figured my ls1 with 8.5:1 compression should be 270 rwhp NA. now at 1st i made 535rwhp on 12psi, now im at 511rwhp. if i am making 270rwhp NA am i where i should be with 12lbs????...if so great all i need is more boost but if im low for 12lbs, i wondering if the motor it self is down on power. i got about 200 miles on rebuild bottom end.

Speed

iTrader: (33)

It isn't really a liner increase in power. 1lb of boost isn't necessarily 1/10 of the airflow of 10lbs of boost.

Mark98SS

iTrader: (1)

I went from 380 cam only to 505 at 7 psi, so about 18 hp per psi. You gained 240 hp on 12 psi = 20 per psi.

30th t/a

iTrader: (51)

correct but im wonder if i should be seeing 23 -25psi/psi

kp

iTrader: (34)

I see like 23rwhp per pound of boost but my motor is pretty weak n/a. 20-25 would be normal I would guess, have to watch them correction factors on the dyno though. A high correction will give higher horespower numbers per psi and some drivetrains suck up more power the others, I wouldnt lose sleep over 20rwhp per psi

LSs1Power

iTrader: (5)

It depends on alot of variables, but from what i gatherd in the thread i listed below is that different kits of FI did manage to yield different gains per boost.
Keep in mind this thread was done along time ago so it might need some updating soon. When i have more free time on my hand i might do just that.

https://ls1tech.com/forums/forced-induction/137685-efficiency-fi-setups-out-there-ii-final-results.html

gametech

iTrader: (1)

The general math should be that you gain 7% of your N/A power per # of boost minus whatever power is robbed in generating that boost. This comes from atmospheric pressure of approximately 15psi, meaning each lb. of boost is about 7% increase over N/A. Of course the power it takes to generate the boost is different for different forms of FI, and if you have to make to many compromises with your timing to avoid detonation you will see a much lower percentage gain.

30th t/a

iTrader: (51)

thanks a trillion! this is the thread i wanted.

nitrorocket

iTrader: (12)

I am making about 25 rwhp per psi. I would say 26-27 rwhp is attainable with a good tune. I had my timing and AFR a little off and still made 25 rwhp per psi.

All depends on the combo for sure!

mulot30th

Its more a question of how is your engine breathe and the supercharger/turbo efficiency per # of boost...

I'd say you can count up to 85% of the increase on hp from N/A (14.7 psi) to boost psi (5 psi for example ) you divide 5 per 14.7 and multiply the result by your N/A Hp and multiply again by 0.85 and you obtain your Hp increase...

but that is an approximation of course!