I measured all my volumes and computer that I will need a .177 shim for each cylinder to give me 8.0:1 on all cylinders. I have a few trhings I can try and do while I wait for them but I hope they get here fast! I will have at least a day or 2 of down time and that is lost production time to me. Engine assembly is going very well. There are some holes in the documentation and DVD but nothing a couple of pestering phone calls to GP doesn't fix.