JE Pistons Ultra Series GM Gen III/IV LS 4.13in Bore/4in Stroke Set of 8 Pistons

When you're building a serious GM Gen III/IV LS engine, especially one that's going to see boost or nitrous, you need pistons that can handle the pressure. This set of eight Ultra Series pistons from JE Pistons is designed precisely for those demanding applications. You get the pistons themselves, ready for your build, with features typically found only in custom setups.

JE Pistons uses their proprietary Aligned Grain Flow forging technology, which maximizes tensile strength to stand up to the extreme cylinder pressures common in power-adder engines. They also come with a thermal barrier crown coating, a ceramic-based material that reflects heat back into the combustion chamber, helping to keep piston crown temperatures down and improving exhaust gas scavenging. The included high-strength wrist pins, made by Trend Performance, are built for the rigors of high-horsepower builds. Plus, the skirt coating reduces friction and wear on the piston skirts and cylinder walls, which also helps quiet down operation, especially when the engine is cold.

These pistons are further enhanced with lateral gas ports, which help maintain a solid ring seal even at high RPMs and under significant boost. Every aspect of the Ultra Series pistons is optimized for high-horsepower racing engines, and they are made 100% in the USA. Keep in mind these are not CARB approved and cannot be shipped to California.