I'm running 11.4 CR with Indy 360-2 230 cc heads, combustion chambers are 65cc. Its set up with zero deck with a 0.40 gasket & JE flat tops. The cam is 260/266 @.050 .675/.675 lift, 108 installed at 104. I run it on the street with 93 pump, at the track with a 50/50 mixture of 101 & 93 just to be on the safe side. So far plugs look good & no problems.