Wiseco Professional Series Subaru EJ257 WRX/STI 99.5mm Bore -19cc Dish Piston Kit (K598M995AP)

Fits Subaru EJ257 engines found in WRX and STI models. This kit provides a professional-grade foundation for high-performance builds requiring the thermal stability and strength of forged 2618 aluminum.

The Wiseco Professional Series piston kit (MPN: K598M995AP) is engineered and machined in the USA to handle the rigors of severe-duty racing. These pistons feature a 99.5mm bore and a -19cc dish volume specifically optimized for the 4-valve EJ257 cylinder head. Each piston is treated with Wiseco’s proprietary ArmorGlide skirt coating to reduce friction, minimize wear, and provide quieter operation. The design incorporates forced pin oiling for enhanced lubrication at the wrist pin and anti-detonation grooves to maintain ring seal integrity under high-boost conditions.

• Forged from 2618 aluminum for maximum tensile strength and heat resistance
• 99.5mm bore size with -19cc dish volume
• ArmorGlide skirt coating for friction reduction and seizure resistance
• Forced pin oiling for superior wrist pin lubrication
• Precision-machined ring grooves and anti-detonation grooves
• Fully machined crown features for optimized combustion
• Kit includes premium rings and pins
• Manufacturer Part Number: K598M995AP