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RB25 with Thinner MLS Headgasket (0.76mm) I've done a lot of searching but haven't found anyone who has tried this before (possibly for a good reason?). My R33 is a track car and I'm rebuilding my RB25DET after cracking a piston ringland, I was running E17 but will be going E85 for the extra safety that offers. For the time being I will be continuing to use standard pistons (with a hone and new rings). I'm considering ARP head studs as I'm getting sick of buying single use OEM bolts (this is the third time the head has come off now) and I'm looking at a MLS head gasket for the same reason. My calculations seem to indicate that going from the stock head gasket (1.1mm compressed) to a 30 thou head gasket (0.76mm) will raise my compression ration to 9.3 which would be a nice bump with E85 use (standard turbo, with plans to go highflow later on). Has anyone attempted this before (or shaved the block for the same effect)? My main concern is the effects this will have on the quench area, I'm using standard cams so valve clearance should be okay.