Originally Posted by Caballerokid
The engine is already built and running with the .125" dome pistons. Those unfortunately won't change as well as the fact they are .025" in the hole. If I run a .041" gasket my quench is trash. This is why I ran the .015" shim gasket to get a .040" quench. Also, with the combination I have currently it is 10.2:1 CR and still detonates because I can't run full timing because of the larger chamber, thus wanting the smaller more efficient chamber. I have easy access to all kinds of fuels where I'm at so if i have to run 100 all day everyday, that will suck but can be done as this is going to be a drift car that isn't driven often enough. Plus if I were to run the aluminum SHP heads, that will be like dropping my compression a full point so I'll be roughly 10.4:1 which isn't too different from where I'm at not but with a more efficient chamber and fast burn rate. I just need to make sure the dome will clear the "heart" shape of the chamber or the pistons will need to be clearanced.
There's no "like dropping my compression a full point" with all the compression you'll have with 64cc chambers you'll require race fuel. E85 may be another option for you, but conversion is costly, though race gas is costly too.