Engines and Components› Pistons and Piston Rings

CP Pistons

Forged Piston Set, 100mm Bore, 9.0:1 Compression Ratio

$885.15

SKU: SC7427

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Overview

The CP Pistons SC7427 is a set of forged aluminum pistons designed for high-performance racing engines. They feature anti-detonation grooves to protect the top ring and a V-shaped accumulator groove to manage blow-by and enhance ring seal. The pistons are fully CNC machined and balanced to +/- 1 gram, with a 100mm bore size and a 9.0:1 compression ratio.

These pistons include piston rings, wrist pins, and circlips. They are constructed from high-strength aluminum forgings and are designed with super lightweight characteristics. Additional features include pin lock grooves for easier lock removal and double pin oilers for improved wrist pin lubrication.
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The CP Pistons SC7427 is a high-strength, forged aluminum piston set engineered for demanding racing applications. CP-Carrillo's pistons are the backbone of serious racing engines, developed through extensive analysis, reverse engineering, and design flexibility to achieve top-tier performance. Each piston is fully CNC machined and precisely balanced to within +/- 1 gram, ensuring optimal engine operation. A V-shaped Accumulator Groove is machined into the 2nd ring land to capture excess blow-by, improve ring seal, and alleviate top ring flutter. Additionally, a Constant Pressure Groove works with lateral gas ports to equalize pressure behind the top ring, keep gas ports clear of carbon, and prevent top land smudging. These pistons also incorporate Double Pin Oilers, which, in conjunction with their dual-fed reservoir, deliver twice the amount of oil from the cylinder wall to the wrist pin for enhanced lubrication. The SC7427 features a 100mm bore size, a 9.0:1 compression ratio, a 1.208" compression height, a 23mm pin size, a 130.5mm rod length, and a 79mm stroke. What's in the box: A set of CP Pistons aluminum forged pistons, including piston rings, wrist pins, and circlips. These pistons are specifically designed for multiple Subaru fitments, including the 2006-2014 Subaru WRX, 2004-2014 Subaru STi, 2004-2013 Subaru Forester XT, 2005-2012 Subaru Legacy GT, 2005-2009 Subaru Outback XT, and the 2004-2006 Subaru Baja Turbo.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandCP Pistons
Part NumberSC7427
CategoryEngines and Components
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Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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