Product Information
Part #: 310927. JE Pistons is excited to present the first billet racing pistons for Subaru EJ257 engines, suitable for your WRX and STI. These pistons were initially developed for the Crawford Performance Unlimited AWD Time Attack Subaru and Ken Block's Gymkhana racecar and are now available to the public. Crafted from high - quality 2618 - T6 wrought aluminum bar stock using 100% CNC machining, they are perfect for high - horsepower road and drag race engines. The pistons feature internal and external bracing, which significantly enhances durability and strength. A special 'donut dish' crown and an application - specific under - crown profile help redistribute heat and reduce stress in high - horsepower Subaru engines. Unlike forged pistons, billet pistons are machined on all surfaces, removing unnecessary weight during manufacturing. This results in a weight reduction of up to 32 grams compared to other piston designs! The set includes high - quality 9310 steel wrist pins and JE Pro Seal Rings. For extreme racing, upgraded Diamond Like Carbon (DLC) coated wrist pins are available. Fitment: SUBARU EJ257 BILLET FSR, STD Bore: 99.5mm. Features: 100% CNC machined billet piston, designed for high - horsepower Subaru racing engines up to 1200hp, weighs only 392 grams (up to 32 grams lighter than other aftermarket pistons), made from high - quality, certified 2618 - T6 aluminum alloy, has internal and external strut braces, comes with premium 9310 steel wrist pins (.905 x 2.250'), DLC upgrade available, includes JE Pro Seal Piston Rings (1.2, 1.2, 2.5mm), has Tru Arc locks for easy installation, and includes 4 pistons and 4 rings.
Using these JE pistons and rings is straightforward. First, make sure your engine is clean and free of any debris before installation. Carefully insert the pistons into the cylinders, following the correct orientation. The Tru Arc locks make installation a breeze. When it comes to the wrist pins, you can use the standard 9310 steel ones that come with the set, or upgrade to DLC coated ones for severe racing. For maintenance, regularly check the pistons for any signs of wear or damage, especially after long - term or high - performance use. Keep the engine well - lubricated to ensure smooth operation and longevity of the pistons. If you notice any abnormal noises or performance issues, it's a good idea to inspect the pistons and rings right away. And always follow the manufacturer's instructions and recommended service intervals for your Subaru EJ257 engine.
