CP Pistons Forged Pistons (Stroker) – Subaru EJ257

CP Pistons – Subaru EJ257 WRX STI Stroker Forged Piston Set

Engineered for high-performance stroker applications, the CP Pistons EJ257 WRX STI Piston Set delivers exceptional strength, reliability, and sealing under high boost, high RPM, and race conditions. Designed to work with an 83 mm stroke and 130.5 mm rod length, these forged pistons suit aggressive street and motorsport Subaru EJ257 builds.

Each piston is manufactured from high-strength aluminium, CNC-machined for precision, and balanced for consistency. Available in multiple bore sizes and compression ratios to suit a variety of tuning goals.

Key Features

• Designed for EJ257 stroker builds with 83 mm stroke
• Forged construction for superior strength and heat resistance
• Matched weight and balanced for high-RPM performance
• Optimised skirt design for reduced friction and wear
• Compatible with 130.5 mm rods and 23 mm wrist pins

Available Variants

Technical Overview

• Stroke: 83 mm (stroker application)
• Rod Length: 130.5 mm
• Compression Height: 1.123 in
• Wrist Pin: 23 mm (0.9055 in), included – 905-2500-18CP1S
• Ring Pack: 1.0 mm / 1.2 mm / 2.8 mm – 905x055 SUB
• Locks: Spiral locks – part numbers vary per piston (e.g. R61568-3917-0)
• Compatible with EJ257 WRX STI engines (stroker builds)