AEM® (06-11) Honda Civic Si Cold Air Intake System with Dryflow® Filter

The AEM 21-685 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 Honda Civic SI and Acura ILX 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 relocated to the driver-side wheel well which is designed to reduce intake air temperature and increase horsepower. The intake tubing is constructed from mandrel-bent aluminum featuring a durable chrome-like finish. This air intake system was developed to accommodate the engine's factory emissions control devices including the mass air flow sensor, a couple replacement silicone breather hoses as well as a replacement radiator 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 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. 

• Increased horsepower
• Tuned and dyno-tested to improve acceleration and engine sound
• Low restriction aluminum tubing
• 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	6.27 HP @ 5100 RPM
Replacement Filter	21-203DK
Air Filter Color	Red
Air Filter Material	Non-woven Synthetic
Air Filter Outlet Shape	Round
Clamps Included	11
Clamp Material	Stainless Steel
Clamp Style	Mini
Couplers Included	None
Product Style	AEM Cold Air Intake System
Intake Pipe Color / Finish	Polished
Intake Pipe Material	Aluminum
CARB EO Number	D-670-21
Street Legal In All US States	Yes
TUV Approved (Europe)	No
Weight	8.2 lb (3.7 kg)
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