The AEM 21-731C 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 Ford Fiesta 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 gunmetal gray powder coated finish. This air intake system was developed to accommodate the engine's factory emissions control devices including the valve cover breather hose. The tapered 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. 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 21-731C vehicle applications to determine the legal status for each vehicle.
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
Estimated Horsepower Gain
7 HP @ 4900 RPM
Air Filter Color
Air Filter Material
Air Filter Outlet Shape
AEM Cold Air Intake System
Intake Pipe Color / Finish
Intake Pipe Material
CARB EO Number
Street Legal In All US States
TUV Approved (Europe)
7.1 lb (3.2 kg)
Product Box Height
8.5 in (216 mm)
Product Box Length
18.25 in (464 mm)
Product Box Width
14.5 in (368 mm)
Mounting Hardware Included
No cross references found for this part
Wrench, Extension, Flat Blade Screwdriver, Allen Wrench
Custom-engineered tubes deliver better airflow than you get with a stock intake. More air means better performance.
Using cotton gauze instead of typical folded paper, our filters increase airflow while providing excellent engine protection.
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