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

This is a set of eight JE Pistons Ultra Series pistons, designed for GM Gen III and IV LS engines with a 4.130-inch bore and a 4-inch stroke. These pistons are built for serious performance, featuring JE's proprietary Aligned Grain Flow forging technology, which maximizes tensile strength to handle the intense cylinder pressures found in boosted or nitrous-fed V8 engines. Every aspect of these pistons is optimized for high-horsepower racing applications.

You'll find several custom-level features included as standard. The thermal barrier crown coating reflects heat back into the combustion chamber, helping to lower piston crown temperatures and improve exhaust gas scavenging. A skirt coating is applied to reduce friction and wear on the piston skirts and cylinder walls, which also helps to quiet down engine noise, especially during cold starts. To ensure consistent ring seal even under high RPM and boost conditions, these pistons include lateral gas ports. They also feature optimized pin oiling to keep the wrist pins and bores well-lubricated, reducing heat and wear. The set includes high-strength wrist pins manufactured by Trend Performance in the USA, built to withstand the demands of power-adder builds.

These pistons are made 100% in the USA. Please note that this part is not CARB approved and cannot be shipped to California.