Subaru EJ257 WRX/STI 4V Piston Set 100mm Bore

The Wiseco Subaru EJ257 WRX/STI 4V Piston Set 100mm Bore is purpose-built for serious Subaru enthusiasts and engine builders tackling high-output builds on the legendary EJ257 platform. Whether you're pushing toward 400+ horsepower or simply replacing worn factory pistons with a proven upgrade, this forged piston set delivers the strength and precision required for aggressive tuning, forced induction, and sustained performance.

Wiseco pistons have earned their reputation in the Subaru community as the go-to choice for reliability when stock components reach their limits. Each piston in this set features Wiseco's advanced forging technology and optimized crown geometry designed specifically for the EJ257's four-valve-per-cylinder head design. The 100mm bore specification maintains factory displacement while allowing precision clearances that accommodate thermal expansion under boost and high engine speeds.

Premium forged aluminum construction, reinforced skirts, and calculated compression ratios ensure these pistons survive detonation, sustained high RPM operation, and elevated cylinder pressures that would destroy stock components. The ring groove design and pin placement are engineered for the EJ257's structural characteristics, providing superior load distribution and minimizing side thrust that causes bore wear. Engine builders, tuners, and WRX/STI owners planning stroker kits, turbo upgrades, or E85 fuel conversion will find this piston set essential insurance against engine failure.