If you bolted those heads on stock and with tha t .039 gaskets you'd be at about 7.8 compression. Mill the heads down to 75 cc and be at about 8.3, switch to a .020 gasket and be at about 8.6. I know 440source says their heads will mill safely to 75cc. There is a formula telling you how much to mill the intake flange on the heads per thou of head milling, I don't know what it is though.