JE Pistons SUB EJ257 83mm STR 99.5mm Bore CR 8.5 KIT Set of 4 Pistons

Starting with a 2618 aluminum forging, these JE Pistons are built for serious performance in your Subaru EJ257 engine. The 3.918-inch bore size and 8.50:1 compression ratio are specifically chosen to optimize power and durability for high-demand applications, whether you're building a track car or a powerful street machine. JE Pistons has been making forged pistons for over 75 years, and they engineer and machine these right here in the USA.

You'll find JE's proprietary Forged Side Relief (FSR) design, which helps reduce friction and save weight by using a shorter wrist pin and narrower skirt. Depending on the specific application, you might also get an accumulator groove to help manage combustion gas pressure, leading to better ring seal and consistent power delivery. Some applications also feature a skirt coating that further reduces friction and noise while protecting the piston skirts and cylinder walls. This kit includes everything you need to get your engine rebuilt: the four pistons, high-quality wrist pins, locks, and JE Pro Seal premium piston rings.

This piston kit is designed for a direct fit in the 2002-2012 Subaru Impreza, as well as select Forester and Legacy models. 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 assembly and break-in procedures.