98" 3-5/8" Big Bore Cylinder and Piston Kit for S&S SH98 Engines or 1966-84 HD® Big Twins With S&S 98" Sidewinder Kit - Gloss Black FinishThis 3 5 8" big bore kit may be used to replace the cylinders and pistons of an S&S SH98 engine or a stock HD shovelhead engine that has been upgraded with an S&S 98" Sidewindert kit. Stock crankcases must be bored to accomodate the 3 5 8" bore cylinders. The kit includes S&S 3 5 8" bore cylinders, 3 5 8" bore forged pistons with rings and wristpins, head gaskets, base gaskets, exhaust gaskets, and instructions. Compression is 8. 9 : 1. The cylinders