I'm thinking on getting some LS6 heads milled(.055)and CNC ported with stock hollow valves(SDPC). How would this stack up against some stageII 5.3's with 11:5:1? I don't plan on changing the cam.

 

go with the ls6 heads. you can always go with a stg III port and get stupud with the motor, because that's the best core out there as of now. if you go with the 5.3 head, it'll work as well now, but your future options are few.
i hate wasting money by doing stuff over again. if for some reason you decided to go with a 434 super stroker, then you already have the core heads and just need more porting and valves which is much cheaper than buying a whole new set and havingthem worked.
until AFR decides to get off their *** and cast some new killer core, the ls6/ 6.0L are the bad boys on the block.
do it right the first time

 

How do you guys think the LS6 heads would perform compared to stageII's(Ls1's). I'm wondering if the stage II 5.3's will make more power?

 

Anyone with more thoughts???

 

Stage II LS1 heads WILL out perform stock LS6 heads. If you port the LS6 heads then they will out perform the Stage II LS1 heads.