Engines and Components› Pistons and Piston Rings

CP Pistons

CP Piston & Ring Set for Subaru EJ257 WRX STi - Bore (99.5mm) - Size (Standard) - CR (8.2) - SINGLE

$246.29

SKU: C00A SC7420-1

In Stock
In Stock
Ships by Jun 11
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Non-Returnable Item
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Description

The CP Pistons SC7420-1 is a set of forged pistons designed for high-performance applications. These pistons feature a 99.5mm bore and an 8.2:1 compression ratio, making them suitable for turbocharged engines. The set includes high-strength aluminum forgings, a super lightweight design, and are fully CNC machined and balanced to +/- 1 gram. They also include accumulator grooves, double pin oilers, and force-fed oil rings.

Fitment

Fitment Guaranteed

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Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

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Specifications

BrandCP Pistons
Part NumberC00A SC7420-1

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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