Im going to be dropping it into my custom 89 chevy scsb. Its bagged, bodydropped, completely shaved with caddy tails and an escalade front clip and I just finished suicideing the doors. Its going to be pretty nice someday whenever I get it done......I plan on running some sort of ram air into the ls1 with a good exhaust.

A rendering of the truck when its done:


I have a few quesitons...are the stock manifolds( I believe these are the aluminum ones...not the later cast style right?) good enough or should I plan to upgrade to some headers?

What kind of hp and torque numbers can i expect...are there any other mods that are recomended to do?

Lastly do I need to have the computer sent out and reprogrammed/tuned? If so what exactly does this do?