I have an 02 Z28 M6 with the following mods:

LT headers, !Cat, Magnaflow
ASP Pully
Ram Stage 2 clutch
Mosar 9inch w/ 4.30
Free Mods
SLP Lid

I am about to put a Comp Cam 228/230 with a set of Patriot Stage II LS6 heads. What do you think about this setup? How much power should it make?

 

The rear end while a good idea will kill your output on the dyno, although it will more than make up for it at the track.

There are a lot of variables but I would think you should be in the area of 420 to the tire.