JE Pistons and Rings 100 Bore 79mm Stroke 9.5:1 Comp Subaru WRX / STI EJ257 2004-2021

Part #: 310938. JE piston designs are crafted for extreme uses, even professional competitions in your Subaru WRX and STI. In high - stress scenarios with high compression ratios, heavy boost, or lots of nitrous, the 2618 aluminum alloy with high tensile strength is a must. Fitment includes SUBARU EJ257 TIME ATTACK 'FSR'. Note: Now compatible with both OEM and aftermarket rods! Some blocks may need clearance for stroker applications. Features: No deburring or prep needed for dome/dish. Made of 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 a .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 contains 4 pistons and 4 rings.

Using these JE pistons and rings is a straightforward process. First, make sure your engine block is clean and ready for installation. Check if your block needs any clearance work for stroker applications. You can use either OEM or aftermarket rods as these pistons are compatible with both. When installing, there's no need to deburr or prepare the dome/dish, which saves you time. The smooth radii on the dome and dishes help the flame travel better for optimal performance. For maintenance, regularly check the pistons and rings for wear and tear. If you notice any issues, it's best to replace them promptly. Keep the engine well - lubricated to extend the life of these parts. And always follow the standard engine maintenance procedures to ensure the best performance of your Subaru WRX or STI.