I've done three Cometic headgasket jobs with stock surfaces, no leaks. Even my short block builder at JMSracing.com said stock finish is fine. Don't know where this urban legend of needing special surfaces came from. Used studs and proper prep, no problems, maybe those with problems are missing steps.
Guess they are trying to cover their butts as far as sealing. Good thing I never read their site since it says to install them dry and I and everyone I know always used copper spray. Goes to show you get different results on different applications.
summit has gaskets with different compressed thickness (.040 .051 .060) . from my understanding the .040 would bump up compression just a hair over stock, and the others would lower it. what is the optimal CR i should go for or what compressed thickness??