Altec

What would be an idea comp. ration on a 4.6 with a 125 shot. I was thinking somewhere in the 10:1 area.

Boost will be in its future, thats where the dilemma comes in to play, is there a happy medium?

The engine is being built with full forged internals and will get a set of aftermarket heads with cams.

thanks guys!

Bitemark46

If boost is in the future then I'd stay around 9:1 or 9.2:1. But if you are going to keep the boost down to a moderate psi you can keep the factory comp and be ok as long as the tune is safe (fat a/f; moderate timing).

-Markl

Dynotune04

same idea. if your not planning on running nitrous for ever then the lower the compression ratio u go with the better it will be for boost. with a 10:1 ratio you wont be able to run as much boost. 6-8 psi the most and thats gonna be pushing it on a stock bottom end

Altec

The internals would be forged. Would that be pushing the block if I wanted to run maybe close to 10psi (10:1 comp)? Im not sure what that would put me at for hp, but ive heard that these blocks arent good past ~500hp

Dynotune04

at that point if your going to have forged internals i would talk to a respected mustang shop and find out what combo for compression to run with the amount of boost you want to run. whos blower are you planning on running?