JE Pistons Ultra Series GM Gen III/IV LS 4.125in Bore/3.622in 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 built for those demanding applications. They feature JE's proprietary Aligned Grain Flow forging technology, which is an in-house process that maximizes the material's tensile strength. This makes them incredibly strong and ready for the extreme cylinder pressures that come with power-adder builds.

Beyond just being strong, these pistons come with custom-level features right out of the box. The thermal barrier crown coating is a ceramic-based material that reflects heat back into the combustion chamber, helping to keep piston crown temperatures down and improving how exhaust gases are scavenged. You also get a skirt coating that works to reduce friction and wear on the piston skirts and cylinder walls, which can also lead to quieter operation, especially when the engine is cold. These pistons are designed with optimized pin oiling to ensure the pin and bores stay well-lubricated, reducing heat and wear. Plus, they include lateral gas ports to help maintain a solid seal on the top compression ring, even under high RPM and boost conditions. Every part of this piston set is optimized for high-horsepower racing engines, and they are made 100% in the USA.

This kit includes eight forged pistons, each designed for a 4.125-inch bore and featuring a 3.622-inch stroke. The kit also comes with high-strength, thick-wall wrist pins manufactured by Trend Performance in the USA, built to handle the rigors of high-performance and power-adder engines. Please note that these pistons are not CARB approved and cannot be shipped to California.