Big bore 81mm. (OS) Piston kit

XS Performance 1st. oversize (81mm.) Forged Big Bore Piston Kit. Piston includes ring set for 1 piston, piston pin(1) and pin clips(2). Forged Piston features: 1. - Valve pockets cut for large valves. 2. - Mos2 treated piston skirts. 3. - Oil channel for enhanced wrist pin oiling. 4. - 20mm. piston pins that are internally tapered to ends for weight reduction. 5. - Lightweight 9:1 piston assembly weight of approx. 340 Grams. Fits to - 1974-84 447 type engines with Big Bore (750cc.) cylinders.