My 318 Build with questions

Trying to work on the CR number for you but there are a number of 'standard' 318 pistons with different compression heights. Do you pistons have 4 valve reliefs on them or are the flat tops? Better yet, do you have a piston part number?

And we'll have to venture a guess on the combustion chamber volume unless you have measured it; I'm guessing 60 cc's.