340 High Compression Pistons
Wait a minute. If he wants domes he needs the 2316 TRW IIRC. I guess I could go pull one and take a pic. That flat top Rob has will make 10.5:1 if you stick it out of the hole.
Better make dang sure what head you have before you drop money on pistons.
I pulled the Arias 13.5:1 Pistons out of my W2 short block and used them in my W5 short block. You just have to mill the quench pad down and be careful because you are technically moving the dome UP in the chamber. I ended up at 16.2:1 and had to massage the domes down to get it back where I wanted.
Know what you have first.