Since my #s are different from sources I found here I am posting the parts I have CCed. The pistons were from stock motors that had original GM gaskets when disassembled. 1972 Head Volume 73 cc 1972 Piston Volume 37 cc 1975 Head volume 77 cc 1975 Piston volume 27 cc Obviously these 75 figures do not add up to 7.9 : 1 CR. The pistons have stock part #s. The only thing I can figure is that Buick was depleting parts bins when putting these last motors together or this was a warrantee short block replacement early in the life of the car. If anyone has a 75 or 76 piston to compare to this, let me know. I have measurments of dept to compare if not able to cc.
