I just want to run this by everyone and see if my thoughts make sense.
I have a LSA blower on a LS3, the blower is 10% overdriven at the crank and fully ported w/ a 90mm throttle body, but the setup only makes 4 psi.
Motor specs:
stock ls3 compression 10.7:1
stock ls3 heads
LS6 Cam
4" Cold Air Intake
1 7/8 longtubes
x-pipe
no cats
Now I realize that boost is a measurment of restriction and that a bigger, better flowing/breathing motor will make less boost for a given supercharger setup compared to a smaller / poorer flowing motor.
My line of thought is that the stock LSA blower on a stock lsa makes 7-8 psi
Adding longtube headers to a stock LSA usually makes the boost drop by 2-3 psi
A slightly larger cam also makes boost drop by a couple psi
A 10% overdive adds 2-3 psi
So I guess my question is as follows:
Am I really flowing enough air that even with my 10% overdive I'm only seeing 4 psi? I thought I'd be around 6-7.
If so, I'm considering changing the upper pulley to spin the blower even faster, future plans include a magnuson heartbeat but I was hoping this would keep me happy for a while.
Does anyone have data as to how much air a stock LSA blower provides at certain RPM's on stock pulley? I know I can look at logs of a stock CTS-V to estimate this but I'm hoping someone may have some flowbench data.
I haven't checked for vacuum leaks with a smoke machine yet (because I don't have one), but I can't hear or see anything obvious.
Thanks