whats a good piston with 9.5 to 9.8 cr and how will cr change when having heads port and polished would this change cr alot

 

Shouldn't chage your CR much if anything having them ported, polished and a valve job. If you mill them down you will get a higher CR. I'm just going to run the SE pistons in mine. Any of the forged pistons are good. Wisecos are the best for any CR. That's my .02

 

All my conversions were done with forged wisecos and I've had no probs with them. CR is hard o figure unless you know the gaskets, how much is shaved etc.