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Cosworth Forged Pistons; Set of Four SUBARU IMPREZA

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Part #: 20004531
Notes: Forged Pistons
Set of Four
MSRP: $867.00
Your Price: $815.27
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Bore 99.5mm
Comp Ratio 9.2:1

This Item Also Available In

Part Number Price Notes & Specs
20001517 $121.59 Notes Piston Rings
Size 100mm
20001515 $103.71 Notes Piston Rings
Size 99.5mm
20003674 $815.27 Notes Forged Pistons
Set of Four
Bore 99.5mm
Comp Ratio 8.2:1
20003675 $815.27 Notes Forged Pistons
Set of Four
Bore 99.75mm
Comp Ratio 8.2:1
20004533 $815.27 Notes Forged Pistons
Set of Four
Bore 100.0mm
Comp Ratio 9.2:1

All Fitments

Year Model SubModel Cylinders Liter Aspiration Eng Desg. Fuel Notes
2006 - 2014 IMPREZA WRX STI H4 2.5 T EJ257 ALL

Product Description

The piston is one of the most important components within the engine. It can be subjected to directional change up to 285 times every second and must withstand acceleration forces of 8500g’s. Cosworth high performance forged pistons are designed and engineered to withstand this type of punishment and still perform. All Cosworth pistons are manufactured using the same methods as our Formula One pistons and include features such anti scuff skirt coating, ultra-strong pins, polished top and patented antidetonation bands. Additionally, each application uses a unique forging to minimize weight and ensure the strongest possible piston design.

Key Features

  • Unique forgings for each application
  • ‘Xylan’ anti scuff skirt coating
  • Polished tops (reduces carbon build up and relieves stress)
  • Manufactured from proprietary alloy (CosAl 010)
  • Ultra strong pin
  • Patented anti-detonation bands

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