CP Piston & Ring Set for Subaru EJ257 WRX STi - Bore (100mm) - Size (0.5mm) - CR (8.2) - SINGLE

Starting with a 100mm bore and a 0.5mm oversize, this CP Pistons set is built for the Subaru EJ257 engine found in the WRX STi. These are forged pistons, which means they are made from a solid block of aluminum that's heated and hammered into shape under extreme pressure. This process creates a much stronger and more durable piston than cast aluminum, making them a popular choice for performance builds where higher cylinder pressures are expected. The 8.2:1 compression ratio is a notable detail, indicating these pistons are designed for engines that will likely see forced induction, like turbocharging, and will be tuned accordingly.

CP Pistons is a well-known name in the performance engine world, and this set reflects their focus on building robust components. The forged construction helps these pistons withstand the increased heat and stress of boosted applications, reducing the risk of failure. When rebuilding or upgrading your EJ257, choosing pistons that can handle the demands of your build is crucial for long-term reliability and performance. This set is intended for single-piston applications, meaning you'll need to purchase the correct quantity for your engine.