MCS-977920 - 4-1/8" bore SSW+ (Super SideWinder Plus). For use with S&S base pattern. Note: Designed for use with S&S engines. Note: Does not include a rocker cover gasket kit. This must be ordered separately.

Fitment:
99-17 S&S T-series (Twin Cam style) & 84-99 V-series (Evo B.T. style) engines with 4-1/8" bore cylinders