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Enhance your Subaru Impreza or WRX/STi with the AEM Induction 21-478C cold air intake system, engineered to boost horsepower and torque effortlessly. This system features an oversized AEM DRYFLOW synthetic washable air filter, designed for outstanding airflow and filtration, which can last up to 100,000 miles before needing service under normal highway driving conditions. The conical filter's high-capacity design ensures consistent performance and ease of maintenance, delivering a noticeable increase in engine power without sacrificing filter longevity.Â
The mandrel-bent aluminum intake tube improves airflow efficiency while maintaining strength and durability, contributing to overall engine performance. A custom heat shield is included to protect the intake air from the high temperatures generated within the engine bay, ensuring cooler, denser air enters the engine for better combustion. The factory fresh air duct attaches seamlessly to the heat shield, simplifying installation and maintaining the vehicle's original airflow path.
This cold air intake system is designed for quick installation, typically taking less than 90 minutes, making it an accessible upgrade for enthusiasts and DIY mechanics alike. Backed by AEM's Lifetime Limited Warranty, this system guarantees quality and performance. Please note this product is not CARB approved and requires acknowledgment of carb regulations before installation. Enhance your vehicle's power output and efficiency with the reliable performance of the AEM Induction 21-478C cold air intake system, specifically designed for 2008-2014 Subaru Impreza and WRX/STi models.
Features:
Fitment:
Subaru Impreza WRX 2008
Subaru Impreza WRX 2009
Subaru Impreza WRX 2010
Subaru Impreza WRX 2011
Subaru Impreza WRX 2012
Subaru Impreza WRX 2013
Subaru Impreza WRX 2014
Subaru Impreza WRX Limited 2010
Subaru Impreza WRX Limited 2011
Subaru Impreza WRX Limited 2012
Subaru Impreza WRX Limited 2013
Subaru Impreza WRX Limited 2014
Subaru Impreza WRX Premium 2009
Subaru Impreza WRX Premium 2010
Subaru Impreza WRX Premium 2011
Subaru Impreza WRX Premium 2012
Subaru Impreza WRX Premium 2013
Subaru Impreza WRX Premium 2014
Subaru Impreza WRX STI 2008
Subaru Impreza WRX STI 2009
Subaru Impreza WRX STI 2010
Subaru Impreza WRX STI 2011
Subaru Impreza WRX STI 2012
Subaru Impreza WRX STI 2013
Subaru Impreza WRX STI 2014
Subaru Impreza WRX STI Limited 2011
Subaru Impreza WRX STI Limited 2012
Subaru Impreza WRX STI Limited 2013
Subaru Impreza WRX STI Limited 2014
Subaru Impreza WRX STI Special Edition 2010
Order Processing
All orders are processed and shipped within 24 hours of purchase (excluding weekends and holidays).
Orders placed after 3:00 PM EST may ship the following business day.
Shipping Methods
Customers select their preferred shipping method and speed at checkout.
Shipping times are determined by the carrier and cannot be guaranteed by us.
Tracking information will be provided once your order has shipped.
Shipping Coverage
If your package arrives damaged, please notify the delivery driver immediately and contact the shipping carrier to file a claim.
You must report any missing or damaged items within 14 days of delivery.
After this time, we cannot be held responsible for lost or damaged items.
Return Window
You have 30 days from the date of delivery to request a return.
After 30 days, we are unable to accept returns, exchanges, or refund requests.
Eligibility
Items must be returned in their original condition—unused, unwashed, and with all tags and packaging intact.
Certain products may not be eligible for return (e.g., special-order items, customized products, or perishable goods).
Items that have been altered, installed, or modified cannot be returned.
Return Process
Contact our Customer Support team to request a Return Authorization (RMA) before sending items back.
Once your return is approved, you’ll receive instructions on where to send the product.
Customers are responsible for return shipping costs unless the item was defective or incorrect.
Refunds
Refunds are issued to the original payment method once the returned item has been received and inspected.
Please allow 5–10 business days for the refund to appear on your account.
In some cases, a restocking fee may apply (if applicable, this will be disclosed during your return authorization).
