What are these Pistons and what's up with my block

@ a .060 overbore, 3.97 x 3.31= 327.79 (Like!)
@ a .090 overbore, 4.00 x 3.31 = 332.76 (Even better!)

Everything is just a sonic check away from being able to do this. The bigger bore helps with compression and better breathing from the cylinder head. A piston greater than 3.97 (.060 over sized) is probably going to be a custom piston. You’ll also need a dome to get any type of reasonable ratio. It might be a bit hard to get over a 10.5-1 ratio.