JE Pistons and Rings 99.5 Bore 79mm Stroke 9.5:1 Comp Subaru WRX / STI EJ257 2004-2021

Part #: 310936. JE piston designs are tailor - made for extreme scenarios, even professional competitions in your Subaru WRX and STI. In high - stress situations with high compression ratios, high boost, or heavy nitrous use, the 2618 aluminum alloy with high tensile strength is a must. Fitment: SUBARU EJ257 TIME ATTACK 'FSR'. Note: Now compatible with both OEM and aftermarket rods! Some blocks may need clearance for stroker applications. Features: The dome/dish needs no deburring or prep. It's made of 2618 T6 high - tensile forged aluminum. The dome and dishes have smooth radii for great flame travel. Ring widths are 1.2 x 1.2 x 2.5mm. It 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. The package has 4 pistons and 4 rings.

Using these JE pistons and rings is straightforward. First, make sure your engine block is compatible. Check if any clearance is needed for stroker applications, especially for some blocks. These pistons are designed to work with both OEM and aftermarket rods. When installing, there's no need to deburr or prepare the dome/dish. Just follow the standard installation procedures for pistons and rings in your Subaru WRX or STI EJ257. As for maintenance, keep an eye on the engine's performance. If you notice any abnormal noises or power loss, it might be time to inspect the pistons and rings. Make sure to use high - quality engine oil to keep the pistons lubricated. And remember, these are built for extreme conditions, so they can handle high compression ratios and high boost, but still, regular checks are important to ensure long - lasting performance.