I have not done the math for compression yet. I'm not sure if the block has been decked & I'm not sure what thickness head gaskets ill have to use yet. Just from past experience with the flat top pistons & 64cc heads I was thinking it might be a little high to just about right, not really sure yet. I would love to get my hands on some reading for these units, especially any parts break downs or operating tolerances. I have definitely been researching alcohol injection too. Since nos cools things down as does the alco inj I was thinking it was kinda redundant having both, or it could be that much more beneficial to have both..idk