JE Pistons are machined by the most advanced CNC machining technologies available. JE forged Pistons are trusted by racers and engine builds for dependability. FSR (Forged Side Relief) slipper forging design accommodates factory stroke and rod length while easily clearing the reluctor wheel. These Heavy-Duty LS7 pistons are designed for extreme levels of Nitrous/Boost (Pin upgrade recommended above 700 HP). CNC-machined ring grooves accept 1.5, 1.5, 3mm rings. (CR calculated with .042 gasket thickness and 0.00″ deck clearence). STOCK ROD MUST BE HONED TO ACCEPT .927″ DIA PIN. MILLING OF ROD BALANCE PAD MAY BE NEEDED DUE TO VARIATION FROM FACTORY.Includes:Pin #927-2250-15-51C (111g)Wire locks #927-073-MWCompression Ratio:64cc 10.1:166cc 10.0:172cc 9.5:1Photo is for illustration purposes only