JE Pistons SUB STI EJ257 100mm Bore CR 8.5 KIT Set of 4 Pistons

When you're building a high-performance Subaru EJ257 engine, the pistons are a critical component. These JE Pistons are forged from 2618 aluminum, a material chosen for its high tensile strength, making them well-suited for the demands of performance applications. They are specifically designed for the EJ257 engine, ensuring an optimized balance of durability and performance for your build.

JE Pistons uses a proprietary Forged Side Relief (FSR) forging design. This design helps reduce friction and power loss by using a narrower skirt and a shorter wrist pin, which also saves weight. Depending on the specific application, these pistons may also feature an accumulator groove to help manage combustion gas pressure, leading to better ring seal and more consistent power. A skirt coating, if included for your application, further reduces friction and wear on the piston skirts and cylinder walls, contributing to quieter operation and longer life. Every set is made 100% in the USA and includes high-quality wrist pins, locks, and JE Pro Seal premium piston rings.

This kit is for a 100mm bore with a compression ratio of 8.5:1, featuring an inverted dome/dish design. It's important to note that these pistons are not CARB approved and cannot be shipped to California. For a complete engine build, ensure you have all necessary supporting components and refer to the manufacturer's installation instructions for proper fitment and assembly.