AEM 21-478WR Cold air intake kit for Subaru Impreza WRX STI 2008-2013 (GRB, GVB) EJ25 –

Increased horsepower

Tuned and dyno-tested to improve acceleration and engine sound

Low restriction aluminum tubing
Easy to install using commonly available tools
Air filter lasts up to 100,000 miles before cleaning is required (depending on driving conditions)
Washable and reusable oil-free filter media
AEM Lifetime Limited Warranty

The AEM 21-478WR fits some Subaru Impreza WRX, Subaru Impreza WRX STi, Subaru WRX, and Subaru WRX STI models. See vehicle applications for details.

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. [More Information on AEM Cold Air Intake Systems]

 AEM 21-478WR Product Specifications

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

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

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)

Horsepower gains based on similar vehicle dynamometer test. Results will vary. 

Details: