Include a set of S&S Shovelhead-style cylinder heads, a pair of S&S stock bore cylinders (3-7/16" for 74" engines or 3-1/2" for 80"), forged 8:1 compression pistons complete with rings and wrist pins, manifold clamps, manifold seals, all required hardware, and gaskets Pistons are pre-fit to the cylinders, so there is no machine work to be done and very little down time Made in the U.S.A.. TOP END KIT 74" 66-78BT