With 6lbs of boost, how much hp should my bone stock 86 GT make? I know there are tons of other mods (heads, intake, gears, etc.) I can do but I'm curious as to what a supercharger alone would put me at.
I remember the first paxtons back in the day made about 35-45% increase at the low boost levels. Not too bad for 5 hours of work. Of course everything that works on a N/A engine works on a S/C engine. A good flowing exhaust setup and ports really help a S/C engine. The intake path does too, but if you can do one or the other, do exhaust. The SC pushes the air through the intake, but the engine must work to push out the exhaust.
Its hard to say, it definatly would help but a good H/C/I with supporting components will do more, but when you do a S/C, you'll be able to make larger gains when you do the heads, cam, and intake, plus you'll be able to go larger also.
I think if I were to start all over again with a bone stock car, I would probally do gears and subframes, then a blower.