I've been told that the 5.7l head is much better suited for porting as opposed to the 6.0l due to GM casting design. Anyone have info on this issue to back this up?

 

I think you have it backwards. Do a search in this section, read some of the posts, and you'll have your answer.

 

I've been told by two engine builders that 6.0l motors are using 5.7l heads due to smaller combustion chamber, yielding higher compression ratios. If you look at the first posting on cc's vs cr's, you will note that exact info. Higher compression ratios along with a good port job will yield much better performance! If you focus on stock heads, they flow better stock. Porting is when they begin to differ. Check it out!

 

fwiw i know patriot uses 6.0ltr cores for their ls6 style ported heads...the have the combustion chambers welded to give you the compression ratio of choice. And I believe you can make them outflow ls1 heads with a good amount of port work pretty easily.

 

when it comes down to it, you will get much more bang for the buck and time if you just buy a set of heads. as soon as i save up some money, i am looking at the afr heads!