CP Pistons – Subaru EJ20 WRX Forged Piston Set CP Pistons' forged piston range for Subaru EJ20 is engineered for turbocharged high-performance builds demanding superior strength and reliability. Designed for a 75 mm stroke and 130.5 mm rod length, these pistons are perfect for street and track setups running elevated boost, RPM, or aggressive tuning. Each piston is CNC-machined from high-strength forged aluminium, featuring an optimised skirt profile and valve reliefs for excellent sealing, efficiency, and durability. Offered in multiple bore sizes with consistent compression ratio (8.5:1), this set caters to rebuilds and oversized applications. Key Features Engineered for Subaru EJ20 WRX and EJ205 engines Designed for 75 mm stroke and 130.5 mm rod length Forged from high-strength aluminium for superior performance Compression ratio of 8.5:1 – ideal for forced induction Balanced weight and optimised dome for power and reliability Available Variants Variant Part # CR Dome/Dish (cc) Bore (mm) Weight (g) 92.00mm / CR 8.5 SC7399 8.5:1 -8.15 92.00 359 92.50mm / CR 8.5 SC7400 8.5:1 -8.26 92.50 365 93.00mm / CR 8.5 SC7401 8.5:1 -9.50 93.00 378 Technical Overview Stroke: 75 mm Rod Length: 130.5 mm Compression Height: 1.285 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. R51313-3622-0) Fitment: Subaru EJ20 WRX / EJ205
