APR Performance Carbon Fiber Rear Diffuser 2004-2007 WRX / 2004-2007 STI | Carbon Fiber Construction | Rear Aero Diffuser

Overview

The APR Performance Carbon Fiber Rear Diffuser is a precision-engineered aerodynamic component designed specifically for the 2004-2007 Subaru WRX and WRX STI models. This diffuser enhances the vehicle’s rear-end aerodynamics by managing airflow beneath the car, reducing turbulence and promoting smoother air transition to the low-pressure zone behind the vehicle. It is ideal for Subaru enthusiasts looking to improve high-speed stability and complement other aerodynamic upgrades such as rear wings and splitters.

Crafted from lightweight carbon fiber, this diffuser reflects APR’s commitment to motorsport-grade quality and functional design. The part is engineered to integrate seamlessly with the Subaru chassis, maintaining OEM-level fitment and finish while delivering tangible aerodynamic benefits. APR’s approach focuses on optimizing airflow to reduce drag and increase downforce without compromising the vehicle’s street usability or aesthetics.

For Subaru owners, this diffuser not only elevates the visual appeal with its carbon fiber weave but also contributes to improved handling at speed by stabilizing rear-end airflow. This aerodynamic refinement supports better traction and balance, especially during spirited driving or track use, making it a practical upgrade for those who demand both form and function from their WRX or STI.

Features & Specifications

This APR Performance Carbon Fiber Rear Diffuser is engineered for 2004-2007 Subaru WRX and WRX STI models and features a lightweight carbon fiber construction. Constructed from high-quality carbon fiber, it delivers enhanced aerodynamic efficiency and downforce for Subaru enthusiasts seeking improved high-speed stability and OEM+ fitment quality.

• Brand: APR
• Product: Performance Carbon Fiber Rear Diffuser 2004-2007 WRX / 2004-2007 STI
• Part Number: AB-820519
• Fitment: 2004-2005 STI, 2004-2005 WRX, 2006-2007 STI, 2006-2007 WRX
• Material: Carbon Fiber
• Finish: Clear-coated carbon fiber weave
• Construction: Molded carbon fiber composite
• Origin: Made in USA
• Surface Finish: Clear coat for UV protection and gloss
• Mounting: Direct bolt-on with included hardware

Key Benefits

• Aerodynamic Performance: Smooths airflow under the car to reduce rear turbulence and increase downforce.
• Lightweight Construction: Carbon fiber material reduces weight compared to OEM plastic components, aiding handling and acceleration.
• OEM+ Fitment: Designed specifically for 2004-2007 WRX and STI models ensuring precise fit and finish without modification.
• Enhanced Stability: Improves rear-end grip and balance at high speeds, complementing other aero upgrades.
• Visual Appeal: Exposed carbon fiber weave adds a motorsport-inspired aesthetic to the rear of the vehicle.
• Durability: Clear-coated finish protects against UV damage and road debris for long-lasting appearance.

What's Included

• 1× APR Performance Carbon Fiber Rear Diffuser 2004-2007 WRX / STI
• Mounting hardware kit
• Installation instructions

Installation & Compatibility

Installation of the APR Carbon Fiber Rear Diffuser is straightforward for those with basic mechanical skills and requires no special tools beyond standard hand tools. It is a direct bolt-on replacement or addition to the factory rear bumper area, designed to fit precisely without trimming or modification. Professional installation is recommended for optimal alignment and finish, especially if combined with other aerodynamic components. This diffuser is compatible with all 2004-2007 Subaru WRX and WRX STI models; verify your specific year and trim to ensure proper fitment.

• Professional Installation: Recommended
• Modifications Required: None
• Verify Compatibility: Confirm fitment for your specific year and trim level

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