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WRX Rear Diffuser, STI Rear Diffuser
Model:  2015-2021 SUBARU WRX/STI REAR DIFFUSER  V7
Fitment: 2015-2021 SUBARU WRX/STI

  • Type: Subaru WRX body kit, STI Body Kit
  • Made from Aerospace Lightweight ALUMINUM no ABS PLASTIC!!!!
  • Comes fully CNC'd and professionally powder coated.
  • Comes pre-drilled
  • Fitment Guaranteed
  • Hardware included
  • Professional install highly recommended

Installation video here

Made in USA
Proudly manufactured in the United States using high-grade materials and expert craftsmanship.

Production Lead Time
CNC items are made to order and have raw materials allocated to production once the order is placed. For concerns regarding current lead times, please review the CNC Products section in our Terms & Conditions.


    A rear diffuser is an automotive aerodynamic modification typically found mounted on the vehicle’s underbody located at the rear of the car, underneath the rear bumper. As a vehicle is in motion, air flowing in the underbody is typically at high-speed and has low-pressure. The design and purpose of a diffuser are to help reduce drag and to create downforce by facilitating the airflow underneath the vehicle’s underbody. A diffuser is used to increase the air volume along its full length, thus creating a void that must be filled by air. This in turn creates a Venturi effect, meaning the air flow is accelerated at the beginning of the diffuser creating a low pressure, thus creating downforce. As the air travels along the full length of the diffuser, the high-velocity air is eased back into standard velocity matching the ambient speed at the rear of the vehicle reducing overall drag. With the addition of vertical “fins” attached to the diffuser, this helps to optimize the diffusers efficiency by ensuring that all air drawn into the diffuser is from the underbody and not from the upper body surfaces. A diffuser can be further tune-up with the addition of a front splitter to help mediate the underbody’s airflow.

    • All Aeroflow Dynamic Exhaust are Built-to-Order with a lead time of 4-8 weeks. Once the order has been placed, it cannot be canceled.

    No Returns for Aeroflow Dynamics Parts

    All sales are final. We do not accept returns or exchanges, except in the case of a defective product. If you receive a defective product, please contact us within 2 days of receiving the product to arrange for a return or exchange.

    To be eligible for a return or exchange due to a defective product, you must provide proof of purchase and the product must be in its original packaging.

    We reserve the right to refuse any returns or exchanges that do not meet the above criteria.

    If you have any questions or concerns about a product before making a purchase, please contact us for more information. We will be happy to assist you.

    By making a purchase on our website, you acknowledge and agree to this no return policy

    Aeroflowdynamics Return Policy

    WARRANTY:

    Warranty covers all defects in materials and craftsmanship over a 30-day period from purchase. Warranty is only applicable to the original purchaser/owner of the item(s). Warranty does not cover items damaged by customer misuse and or abuse. Aeroflowdynamics is NOT responsible for any and all damages caused by the improper installation of any product. Please mail sales@aeroflowdynamics.com with any questions in regards to warranty.

    If the package arrived damaged, please notify us within 48 hours of when you receive the package. After the 48 hours, we will not be able to offer a refund or ship you a replacement.

    Aeroflowdynamics Warranty

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    AeroFlow Dyanmics

    AeroFlow Dynamics is a California-based automotive parts company specializing in high-quality, precision-engineered aluminum aerodynamic upgrades such as splitters, wings, diffusers, fender flares, and overlays. Their products are CNC-machined from aerospace-grade aluminum, powder coated for durability, and proudly made in the USA with strict quality control. They offer components for a wide range of makes and models, including Subaru, Honda, Toyota, BMW, and more.

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