JE Pistons and Rings 99.75 Bore 79mm Stroke 9.5:1 Comp Subaru WRX / STI EJ257 2004-2021

Part #: 310937. JE piston designs are crafted for extreme Subaru WRX and STI applications, even professional competition. High compression ratios, high boost, or heavy nitrous use call for the 2618 aluminum alloy with high tensile strength. Fitment: SUBARU EJ257 TIME ATTACK 'FSR'. Note: Now compatible with either OEM or aftermarket rods! Some blocks may need clearing for stroker applications. Features: No deburring or prep needed for dome/dish. 2618 T6 high - tensile forged aluminum. Dome and dishes have smooth radii for great flame travel. Ring widths are 1.2 x 1.2 x 2.5mm. Comes with .905 x 2.500 (Round Forging) and .905 x 2.250” (FSR Forging) straight - wall carbon steel wrist pin. Pin fitting and Tru - Arc locks are included. Package has 4 pistons and 4 rings.

These JE pistons and rings are designed for Subaru WRX and STI EJ257 engines from 2004 to 2021. When installing, make sure to check if your engine block needs clearing for stroker applications. You can use either OEM or aftermarket rods with these pistons. The pistons don't need any deburring or preparation of the dome/dish before installation. For maintenance, keep the pistons clean and check the ring widths regularly. If you notice any wear on the wrist pins or the Tru - Arc locks, replace them promptly. Store the pistons in a dry place to prevent corrosion.