When you pull the engine down CC the heads and check how far in the hole the pistons are so you can calculate compression. 9.5 pistons don't mean a whole lot on a Pontiac, chamber size is everything along with a dish or valve reliefs in the piston tops.
If it's an 092 head you could end up around 10.5:1 with a flat top.
Wanting a Custom fit in an off the rack world.
I don't have time for a job, I just need the money.
