so the car is only going to pick up 5-10? Damn, on my 331 stroker I saw gains of 20hp with the x-pipe and 8 from catback. Are the stock one's pretty good then? I am almost afraid to ask what a cold air intake would net.
You're best bet is to do long tube headers, catback, x-pipe, and cold air intake at the same time. You should pick up 30 rwhp with those mods. Get a tune and you'll do a little better. When I added my catback on my stock motor...I didn't pick up anything but a loud exhaust. :lol:
I just re-read your first post...you might pick up a little more with it being a C5 and not a Z06...won't be much more though. :cheers: