I did a search and didnt have much luck. Iv'e been looking at some performance cylinder heads and want to know what size chamber to get or what to mill too. I'd like to go fairly high and just run 93. i was thinkin 10.8-11:1. How many CC's does it take to drop to gain a point in compression? How far do you think I should go? I will go with a more agressive cam too. Its a stock 5.3 short block.

 

About .042" will drop you about a full point with stock gaskets. I know .045" is about all I'd go, maybe .050" no more though. More than that and you have fitment problems with the intake not aligning with the intake ports.