JE Pistons SUB STI EJ257 100mm Bore CR 9.5 KIT Set of 4 Pistons

Forged from 2618 aluminum, these JE Pistons are built for high-demand performance applications. This set is specifically designed for the Subaru EJ257 engine, featuring a 100mm bore and a 9.5:1 compression ratio. JE Pistons brings over 75 years of experience to the table, engineering, forging, and machining these pistons 100% in the USA to offer a durable and high-performing component for your build.

The proprietary Forged Side Relief (FSR) design helps minimize friction and power loss by reducing skirt width, and a shorter wrist pin further saves weight. Depending on the specific application, these pistons may include an accumulator groove to reduce combustion gas pressure, which helps prevent ring flutter and improve ring seal for consistent power delivery. A skirt coating, also application-dependent, can reduce friction and wear on the piston skirts and cylinder walls, while also contributing to quieter operation.

This kit includes everything you need to get these pistons installed: high-quality wrist pins, locks, and JE Pro Seal premium piston rings. JE Pistons are proven on the track, from drift to drag, and are a solid choice when you need the best in forged pistons for your performance Subaru.