Mahle Pistons PowerPak 99.5mm Bore 8.5:1 Comp Subaru WRX / STI EJ25 2004-2021

Pistons PowerPak 99.5mm Bore; 3.11 Stroke; 5.137 Rod; 23mm Pin; 1.209 C/D; 8.5:1 Compression Ratio; -22cc DomeVolume; 399 Gram Weight [Subaru Impreza(2004-2007)]

The Mahle PowerPak is a complete, race proven piston assembly kit composed of hand deburred, forged, performance coated pistons, high quality steel pins, round wire locks, and low drag performance rings. We race Mahle forged pistons in our dragster and highly recommend them for their strength and high quality GRAFAL coating.

Features: Forged Aluminum Pistons CNC machined crown, Hand deburred finishing, Forced pin oiling with machined drain backs, Lightweight slipper skirt forgings, CNC finished pin bores, Race Proven reliable round wire locks, and Pre-fitted German steel high strength pins. Mahle's ultra flat ring grooves and low drag rings offer improved sealing

Improved coating for less friction. The piston skirts on Mahle pistons are coated with GRAFAL by Mahle. This coating helps to reduce friction, increase scuffing resistance while improving durability and enable a closer fitting piston to wall clearance for significantly lower engine noise.