CP Piston & Ring Set for Subaru EJ25 WRX STi - Bore (99.5mm) - Size (STD) - CR (10) - Set of 4

This CP Piston Set features a 99.5mm bore and a 10:1 compression ratio. It is designed for enthusiasts seeking reliable power gains, offering superior performance and durability. Engineered to handle high lift cams and oversized valves, this piston set is ideal for high-performance builds and engine upgrades. The pistons are fully CNC machined and balanced to within +/- 1 gram, ensuring precision and smooth operation. They are made from high-strength aluminum forgings and include deep valve reliefs, custom skirt cam and barrel design, accumulator grooves, and high-performance rings. Wrist pins and pin fittings are included, along with double pin oilers and force-fed oil rings to enhance lubrication and longevity.