CP Piston & Ring Set for Subaru EJ257 WRX STi - Bore (100.0mm) - Size (+0.5mm) - CR (9.0)

If you're rebuilding the engine in your 2004-2012 Subaru Impreza WRX STI, especially if you're pushing more power, a strong set of pistons is crucial. This forged piston and ring set from CP Pistons is built to handle the demands of a performance engine. They feature a 100.0mm bore and are 0.5mm oversize, designed to replace stock pistons with a more robust option.

CP Pistons are well-known in the performance world for their durable construction. These pistons are forged from high-strength aluminum, which is significantly stronger and more resistant to detonation than cast pistons. This set is designed for a 9.0:1 compression ratio, making it a solid choice for builds that involve turbo upgrades or other modifications where increased cylinder pressure is expected. The included rings are matched to ensure a proper seal, which is vital for both power and engine longevity.

When installing these, remember they are an oversize part, so proper cylinder wall preparation and honing are essential for a good fit and optimal performance. This set is a significant upgrade for anyone looking to build a reliable, high-performance EJ257 engine. Please note that this part is not CARB approved and cannot be shipped to California.