The MAHLE PowerPak is a complete, race proven piston assembly kit composed of hand deburred, all forged, performance coated pistons, high quality steel pins, round wire locks and low drag performance rings. Performance coatings include a phosphate dry lubricant that is used to protect against ring micro-welding and pin galling during initial startup and break in. For added performance, MAHLE applies it's proprietary Grafal anti-friction coating to each piston skirt. The MAHLE PowerPak was designed as a completely finished drop-in piston assembly. Other than filing the included performance ring set, everything else is done for you. * Forged from 4032 low expansion aluminum alloy for high strength and reduced piston to wall clearance * Radiused valve pockets * Forced Pin Oiling * Precision Pin Fitting and Race Proven Round Wire Locks included * 22mm high quality steel wrist pin (112 grams) included * Precision Ring Grooves for 1.2, 1.2, 2,8mm rings included Piston Specifications: - Stroke: 100mm - Rod Length: 150mm - Pin Diameter: 22mm - Compression Height: 28.7mm - Dome Volume: -19cc - Weight in Grams: 85.5mm = 302, 86mm = 307 - Compression Ratio: 9.0:1