94-1213X 3-5/8 bore piston rings. +.030"

This S&S chromoly replacement piston ring set is designed to fit Evolution and pre-Evolution engines equipped with a 3-5/8 inch big bore kit. These rings are compatible with S&S kits as well as other manufacturers, like Axtell, provided they use the same 1/16 inch compression rings and 5/32 inch oil rings. Getting the ring gap right is critical for engine longevity; a gap that is too tight can lead to seizure, while one too wide loses compression. For street engines, S&S recommends a gap of .004 inches per inch of cylinder diameter. This set provides everything needed for a two-cylinder refresh, ensuring your big bore motor maintains peak efficiency and performance.