I've heard of this but dont get why? What does it do? Does this make any power? I have a 5.7L Zo6 engine in my truck would this make more power on my engine? If it does what will I have to do?

 

5.3 heads will raise your compression on the 5.7

 

Ill switch you my heads for your LS6 heads, .

 

How much power are we looking at here? No thanks i have the heads off my old engine. If it isnt much I wont bother.

 

i think your heads flow better....i wouldn't worry about it, unless youre gonna port and polish them

 

just helps to bump comression. its probably only worth around 20-30 horsepower, but if your squeezing th juice or supercharging in the future most definetly dont mess with it.

 

remember the ls-6 heads have smaller combution chamber than the standard 5.7 ls1 heads (64cc ls-6, 61cc 5.3, 67cc ls-1, 71cc 6.0L) the ls-6 heads outflow the 5.3's and have bigger valves. a CNC ported 5.3 will outflow a stock Ls-6 but a ported ls-6 will kill a 5.3 CNC head. the ls-6 to 5.3L head would only bump you .3 points of compression. the smaller valves and less flow will net you less HP.

 

Ok, enough heard, I'll Port and Polish my heads. thanks for all the info.