Perrin Air Oil Separator Red 2002-2021 WRX / 2004-2021 STi | Ceramic-Coated CNC Machined | Engine Health Component

Overview

The Perrin Air Oil Separator (AOS) is a precision-engineered solution designed to remove oil vapors from crankcase gases before they enter the intake manifold on Subaru WRX and WRX STI models from 2002 through 2021. By capturing and separating oil mist, this component helps prevent carbon buildup inside the intake tract, which can degrade engine performance and longevity. This product is ideal for Subaru enthusiasts looking to maintain engine health, especially those running modified or high-mileage vehicles where crankcase ventilation can become a concern.

Crafted with a ceramic-coated, CNC-machined aluminum body, the Perrin AOS combines durability with efficient oil separation. The ceramic coating provides corrosion resistance and thermal stability, while the precise machining ensures a perfect fit and reliable operation. Perrin Performance’s focus on quality and Subaru-specific engineering means this AOS integrates seamlessly with factory PCV systems without compromising reliability or drivability.

Installing the Perrin Air Oil Separator offers tangible benefits such as reduced intake manifold contamination, improved throttle response, and extended engine life. For Subaru WRX and STI owners, this translates to a cleaner combustion environment and more consistent performance over time. Its robust design supports both daily driving and spirited use, making it a practical upgrade for maintaining the health of your turbocharged Subaru engine.

Features & Specifications

This Perrin Performance Air Oil Separator is engineered specifically for 2002-2021 Subaru WRX and 2004-2021 WRX STI models. Featuring a ceramic-coated, CNC-machined aluminum construction, it delivers effective oil vapor separation to protect your engine and maintain intake cleanliness.

• Brand: Perrin Performance
• Product: Air Oil Separator Red 2002-2021 WRX / 2004-2021 STi
• Part Number: PSP-ENG-620RD
• Fitment: 2002-2003 WRX, 2004-2005 STI, 2004-2005 WRX, 2006-2007 STI, 2006-2007 WRX, 2008-2010 STI, 2008-2010 WRX, 2011-2014 STI, 2011-2014 WRX, 2015-2021 STI, 2015-2021 WRX
• Material: CNC-machined aluminum
• Finish: Ceramic-coated red
• Construction: CNC machined with ceramic coating
• Origin: Made in USA

Key Benefits

• Engine Health: Reduces oil vapor contamination in the intake manifold, minimizing carbon buildup and preserving engine performance.
• Durability: Ceramic coating protects against corrosion and heat, ensuring long-lasting reliability under demanding conditions.
• Fitment: Precision CNC machining guarantees a perfect fit for Subaru WRX and STI models across multiple generations.
• Maintenance: Helps maintain cleaner intake components, reducing the frequency of intake cleaning and valve maintenance.
• Performance Support: Supports consistent throttle response by preventing oil vapor buildup that can affect airflow and combustion.
• OEM Integration: Designed to work seamlessly with factory PCV systems without requiring modifications.

What's Included

• 1× Perrin Air Oil Separator Red 2002-2021 WRX / 2004-2021 STi
• Mounting hardware
• Installation instructions

Installation & Compatibility

Installation of the Perrin Air Oil Separator is straightforward for those with basic mechanical skills and common hand tools. It replaces the factory PCV oil separator and connects to existing vacuum lines without modification. No special tools are required, and the process typically takes under an hour. This product is compatible with stock and lightly modified WRX and STI engines within the specified model years. No tuning is required after installation, making it a practical upgrade for daily drivers and enthusiasts alike.

• Professional Installation: DIY-friendly
• Modifications Required: None
• Verify Compatibility: Confirm fitment for your specific year and trim level before purchase

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