The piston "upgrade" is not an upgrade at all. There are two main pistons for the 360. Flat top and dished. The dished has a taller compression height and basically has the same compression. Although it sits higher in the bore at TDC, it has a dish, which reduces compression. The flat top has a shorter compression height and no dish. There are essentially different types of pistons that achieve basically the same thing. Different year model pistons. There WAS a 1971 only piston from Chrysler that was a flat top and near zero deck height that had an actual 9:1 compression for the 71 only model year, but those pistons are impossible to find in the aftermarket now. You DO NOT have a high compression piston, so stop digging for it. I don't understand your reasoning for returning the heads at all, as you've been told time and again that a low compression engine can be built to run and run strong. You're just not listening. It's your baby though, so have at it.
