Manley 04+ Subaru WRX STi (EJ257) 83mm Stroker 100mm +0.5mm Bore 8.5:1 Dish Piston Set with Rings

When you're rebuilding the engine in your 2004-2012 Subaru Impreza, especially if you're aiming for more power or durability, this Manley forged piston set is what you'll want to consider. This kit includes the pistons, rings, and wrist pins needed to get your EJ257 engine back in top shape. These aren't just stock replacements; they're built to handle more stress and deliver better performance than the original equipment.

Manley uses 2618 alloy forgings for these pistons, which are known for being strong and reliable, especially when you're pushing your engine hard. They've also got proven cam and barrel skirt profiles that help them work smoothly with your cylinder walls while still making good power. The ring lands and grooves are machined to very strict standards, which is key for getting a good seal from your piston rings. A good seal means better compression and more power. The included wrist pins are made from Chrome Moly, a tough material that holds up well under pressure.

This set is specifically designed for a 100mm stroke with a +0.5mm bore, giving you a total bore of 83mm and a dish volume that results in an 8.5:1 compression ratio. This setup is popular for builds looking for a balance of power and reliability. Keep in mind that these pistons are not CARB approved and cannot be shipped to California. Always refer to the manufacturer's installation instructions for proper fitment and assembly procedures.