JE Pistons Ultra Series GM Gen III/IV LS 4.075in Bore/3.622in Stroke Set of 8 Pistons

JE Pistons is well-known for building strong, reliable internal engine components, and their Ultra Series pistons are a prime example of that commitment. If you're building a GM Gen III or IV LS engine that's going to see serious boost or nitrous, these pistons are designed to handle the extreme cylinder pressures that come with those power adder builds. They feature a 4.075 inch bore and a 3.622 inch stroke, with a flat top design and a -5.00 cc volume, making them a solid choice for high-horsepower applications.

What sets these Ultra Series pistons apart is JE's proprietary Aligned Grain Flow forging technology, which maximizes tensile strength to withstand the intense stresses of performance engines. You also get custom-level features right out of the box, like a thermal barrier crown coating that reflects heat back into the combustion chamber, helping to reduce piston crown temperatures. The skirts are coated to reduce friction and wear on both the piston and cylinder walls, which also helps quiet down operation, especially when the engine is cold. Plus, they include lateral gas ports to help maintain a strong ring seal even at high RPMs and under heavy boost, and they come with high-strength, thick-wall wrist pins from Trend Performance.

This set includes eight pistons, each made 100% in the USA. Keep in mind these pistons are not CARB approved and cannot be shipped to California. For serious LS engine builds pushing the limits, these JE Ultra Series pistons offer a well-built foundation.