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

JE Pistons uses a proprietary Aligned Grain Flow forging process for these Ultra Series pistons, which significantly increases their tensile strength. This makes them a solid choice for high-stress engine builds, especially those using power adders like turbochargers or nitrous oxide. The pistons are designed for a 4.000-inch bore and a 4-inch stroke, common in GM Gen III and Gen IV LS engines.

Beyond the strong forging, these pistons come with features usually found only in custom builds. They have a thermal barrier crown coating that reflects heat, helping to keep temperatures down and improve how exhaust gases are scavenged. The skirts are coated to reduce friction and wear against the cylinder walls, which also helps quiet down the engine, particularly during cold starts. Lateral gas ports are included to help maintain a strong seal on the top compression ring, even under high RPM and boost conditions. They also feature enhanced pin oiling to keep the wrist pins and bores well-lubricated, reducing heat and wear.

These pistons are made from 2618 aluminum and include high-strength wrist pins manufactured by Trend Performance. The kit is designed for 8-cylinder engines and includes pistons with an inverted dome, which has a volume of 12.20cc, suitable for specific compression ratio targets. It's important to note that these pistons are not CARB approved and cannot be shipped to California. All JE Pistons products, including this set, are made 100% in the USA.