AEM® (08-14) WRX STI Cold Air Intake System with DryFlow® Filter
AEM® (08-14) WRX STI Cold Air Intake System with DryFlow® Filter
AEM® (08-14) WRX STI Cold Air Intake System with DryFlow® Filter


AEM® (08-14) WRX STI Cold Air Intake System with DryFlow® Filter

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    Compatible: (2.5L)

    2008 - 2014 Subaru WRX STI 







    The AEM 21-478WR Performance Cold Air Intake System produces horsepower and torque gains by replacing your vehicle's restrictive factory air filter and air intake housing. This air intake system was designed, tuned and dyno-tested to fit specific Subaru WRX, WRX STI, Impreza WRX and Impreza WRX STI models. Air enters the system through an oversized AEM Dryflow synthetic washable air filter for outstanding air flow, filtration and performance. The air filter is located in the original air box space and is protected by a heat shield which is designed to reduce intake air temperature and increase horsepower. The intake tubing is constructed from mandrel-bent aluminum featuring a durable textured red powder coated finish. This air intake system was developed to accommodate the engine's factory emissions control devices including the mass air flow sensor. The cylinder shaped AEM Dryflow air filter is made from an oil-free, synthetic filter media that can be used for up to 100,000 miles before cleaning is needed (depending on driving conditions). The air intake system is easy to install with commonly available tools and it is backed by AEM's Lifetime Limited Warranty. Some AEM air intakes are not legal for sale or use in California and other states adopting California emission standards while others are 50 state legal. View the 21-478WR vehicle applications to determine the legal status for each vehicle.

    Estimated Horsepower Gain 36 HP @ 5300 RPM
    Replacement Filter 21-2029DK
    Air Filter Color Red
    Air Filter Material Non-woven Synthetic
    Air Filter Outlet Shape Round
    Clamps Included 3
    Clamp Material Steel
    Clamp Style Regular
    Couplers Included None
    Product Style AEM Cold Air Intake System
    Air Filter Height 9.125 in (232 mm)
    Intake Pipe Color / Finish Wrinkle Red
    Intake Pipe Material Aluminum
    CARB EO Number D-670-21
    Street Legal In All US States Yes
    TUV Approved (Europe) No
    Weight 7.4 lb (3.3 kg)
    Air Filter Large End Diameter 6 in (152 mm)
    Product Box Height 12.25 in (311 mm)
    Product Box Length 20.25 in (514 mm)
    Product Box Width 12.25 in (311 mm)
    Mounting Hardware Included Yes
    Warranty Limited Lifetime


    Install Guide: