Did you say NOS pistons? So..you are going to spray? I would think that a 1/16th NOS ring package would be in order Skinny rings are hot right now and make more HP but in a Spray Motor?? Not me.. Gapless has never shown me more HP on the dyno--they make great leak down test--I would maybe use them in dirt track engines that eat lots of dirt , hoping it might delay fresh up a little but even that is big maybe I think from all I have seen and built it is a gimmick and and expensive one!
