JE Pistons SUB STI EJ257 99.5mm Bore CR 9.5 KIT Set of 4 Pistons

This kit gets you four forged pistons, complete with high-quality wrist pins, locks, and JE Pro Seal premium piston rings, ready to go into your Subaru EJ257 engine. These aren't just any pistons; they're built by JE Pistons, a company with over 75 years of experience making pistons for racing applications. They're forged and machined right here in the USA from 2618 aluminum, which gives them the strong tensile strength needed for high-performance engines.

JE Pistons uses a unique Forged Side Relief (FSR) design that helps reduce friction and save weight by using a narrower skirt and a shorter wrist pin. Depending on the specific application, you might also find an accumulator groove, which helps manage combustion gas pressure to keep the rings seated properly for consistent power. Some applications also include a skirt coating to further reduce friction and wear on the cylinder walls, which can also quiet down the engine operation. These pistons are specifically designed for the EJ257 engine to give you optimized performance and durability.

Because these are high-performance forged pistons, they are designed for demanding use. Please note that this kit is not CARB approved and cannot be shipped to California. Always refer to the manufacturer's installation instructions for proper fitment and assembly procedures.