Pistons to raise Compression Ratio

Exactly. Unless your cam is of a generous duration......
I plan on running a pretty heavy cam. I will be running ported Eddy heads, and would like to keep the compression up around 10:1. I am shooting for around 500hp, I'd like the car to be dangerous to drive, and fast. Modern fast. The 340 ran great, but it's been together since the 80's and popped a head gasket. Not an original 340 car (318) so I don't feel bad going Magnum and roller... and serpentine. I really need to get the block to the machine shop, and let them measure how far down in the hole I am right now. The block may need cleaned up on the deck anyway. I hope it doesn't for labors sake and getting the intake milled costs money id rather spend on the roller rockers anyway. I need to let my machine shop take a look at her. The bores look great imo, and hopefully I can get away with a hone and run standard. Should have block completely torn down tonight, and at the machine shop tomorrow. I've noticed most of the pistons are around $350 for hypereutectics so that works for me. Cam selection will depend on vacuum. I picked up a second hand MSD Atomic for $900. I love the thing, but it is vacuum limited, and they only recommend cams up to 250 duration. Realistically i'd keep it around 234 int 244 ex. Not sure if it being a roller will impact that number much, but I have a lot of figuring to do.