I am thinking of rebuilting my 93 LT1 m6 and I want to add good heads and cam. How much hp have you guys seen from just from that set up. Is it possible go get 360-400rwhp from it. I don't have headers, how much would they make a difference.

 

Depends how serious of a rebuild you want. 350-400 rwhp should be no problem for a heads and cam car. But you'd definatly need headers.

Although you could go more serious build. A friend of mine has a built 355, 227 AFR's, and a huge solid roller and runs flat 10's with a Jerrico 4 speed in his 69 Firebird. Although it does spin 9000 rpm, have a 14:1 compression ratio, and runs on methanol.

 

Take a look at these.
http://store.summitracing.com/defaul...287-1&x=17&y=8
I know you asked about heads and cam only but the intake isn't that much. 425 at the block puts you right in your RWHP target.

You could probably get the whole thing cheaper some where else.

BTW this has the hot cam which is a step up from the original LT4 cam. Although I still don't see where they get the projected HP from. Watch out for fuel rail requirements also. I thought the LT4 intake was only compatible with 94 and up fuel rails(not sure). You could get them very easily at any wrecking yard if such is the case.

 

www.advancedinduction.com
makes it very possible