for Twin Cam 88, aluminum, Over-/Undersize: ±0.0 ”, bore: 3-7/8 ”, with piston rings, gross weight: 1.4 kg These forged pistons are designed to increase displacement of stock TwinCam88 88 engines to 95 cui. (from 1450 auf 1550 cc) with a slight compression increase to 10.4 : 1 with stoc