JE Pistons Ultra Series GM Gen III/IV LS 4.07in 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 4.070-inch bore and a 4-inch stroke. You get the pistons themselves, along with high-strength wrist pins from Trend Performance, all manufactured 100% in the USA. These pistons are built to handle the intense cylinder pressures found in boosted or nitrous-fed V8 engines.

What sets these Ultra Series pistons apart is JE's proprietary Aligned Grain Flow forging technology. This process maximizes the material's tensile strength, making them incredibly robust for high-performance applications. They also come with custom-level features usually found only in fully bespoke builds. The thermal barrier crown coating helps reflect heat, keeping piston crown temperatures down and improving how exhaust gases are scavenged. For reduced friction and wear on the skirts and cylinder walls, especially noticeable during cold starts, they have a special skirt coating. Plus, lateral gas ports are included to help maintain a strong ring seal even at high RPMs and under significant boost.

These pistons are optimized for high-horsepower racing engines, and the enhanced pin oiling features ensure the pin and bores stay well-lubricated, reducing heat and wear. Keep in mind that these are not CARB approved and cannot be shipped to California. For any specific installation details or warranty information, it's always best to consult the manufacturer's documentation.