Part #: 930285127
Mahle’s PowerPak piston assemblies for the Subaru WRX and STI includes forged pistons, piston rings, pins, and wire locks–all in one race-proven package. The pistons are hand-deburred and then coated with dry phosphate to protect against ring micro-welding and pin galling during initial startup. For additional performance, Mahle added its proprietary Grafal anti-friction coating to the piston skirts. Low drag rings, steel pins, and round wire locks complete the Mahle PowerPak package.
Specs:
- Bore (in):3.917 in.
- Bore (mm):99.750mm
- Piston Style:Dish, with four valve reliefs
- Piston Material:Forged aluminum
- Compression Distance (in):1.209 in.
- Piston Head Volume (cc):+22.00cc
- Wrist Pin Style:Press-fit or floating
- Pin Diameter (in):0.906 in.
- Gapless:No
- File Fit:No
- Top Ring Thickness:1.2mm
- Top Ring Material:Steel
- Top Ring Facing Material:Gas nitrided
- Second Ring Thickness:1.5mm
- Second Ring Material:Iron
- Second Ring Facing Material:Cast iron
- Oil Ring Thickness:2.8mm
- Oil Ring Material:Stainless steel
- Oil Ring Tension:Standard