Twin-charged Bonneville Update
I finally put some miles on it and worked out all the kinks, slow turbo oil return, leaking op gasket, crack prone rear header... I bought a rear turbo Powerlog from ZZP and modified the outlet to fit my existing turbo uppipe.
I took it to the dyno last night and made some good runs. But I kept hitting a wall at 5500rpm. I didn;t have my scanner with me at the dyno, so it was not until today I found out the knock ret attack rate was still set to stock value. It was pulling 12deg at 5500 and levelled of at what the scanner showed was 0deg timing, but I know was about -4deg atdc.
Still, it made 376whp at 5500 with a combined 15psi (turbo making 7psi max). I drove the car today before making changes and you could definately feel it fall flat at 5500. I made a few changes, went back on the road and WOW it pulls hard all the way to the MSD-induced 6250rpm rev limit. With only .5-1.3deg KR. That'* with only water in the intercoolers (twins). I have not installed the ice tank in the trunk yet.
Here'* the dyno graph. You can see it hit the wall. Also, you can extrapolate using the hp curve and see if you come up with what it is probably making currently. (390-400whp is my guess.)
There is alot more in it at this state of tune. I am running 11.5:1 a/f and as I said, ambient air temp/water temp in both i/c'*. (which was about 72deg last night) It'* running 12.5deg timing, too which is very conservative for this setup.
1988 Grand Am SE 2.0 Turbo
1996 Bonneville SSEi Twin-Charged