I have a SBC 406 shortblock assembled with forged flattop pistons block is stock decked and was wondering how much compression will I have with 64cc and 70cc heads using FelPro 1014(.039" thick) and will there be a big difference in using the 70cc heads from the 64cc I have always used 64cc heads in the past I can get a NEW set of Edelbrock 60739 Aluminum heads for like $500 from a friend or should I go with the 64cc heads for more power and torque, the cam is a Comp Cams Magnum Hyd. Roller with 224/224 duration at .050" with .525/.525 lift on 110 LSA?THANKS