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05/26/2029 9:32 PM
Tax Return Sale Price $425.31
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Part number: 21-686P
Call For Availability: 800-299-1028
Product Details
AEM 21-686P Cold Air Intake System
Products specifications
Color Polished
Filter Color Red
Filter End Cap Finish Black
Quantity Sold as a kit.
Sleeve Color Black
Tube Color Polished
Tube Material Aluminum
Clamp Material Steel
Clamp Style Regular
HP Increase 4 HP
Intake Pipe Color / Finish Polished
RPM 3800
Clamps Included 9
Estimated HorsePower Gain 4.0 HP @ 3800 RPM
Product Style AEM Cold Air Intake System
Replacement Filter 21-201DK
Air Filter Color Red
Air Filter Height 5.125 in (130 mm)
Air Filter Large End Diameter 6 in (152 mm)
Air Filter Material Non-woven Synthetic
Air Filter Outlet Shape Round
Couplers Included 0
Intake Pipe Ports All intake tube ports needed for the specified applications are included
Mass Air Flow Sensor Adapter Included Mass Air Flow Sensor Adapter Included When Required
Vacuum Tubing Included No
Weight 10 lb (4.5 kg)
Case Length 20.2500
Case Height 12.2500
Case Weight 10.0000
Case Width 12.2500
AEM 21-686P Cold Air Intake
NOT CARB Exempt - No CARB EO #

AEM pioneered the Cold Air induction system for sport compact cars in 1994.

A Cold Air intake system relocates the filter outside of the engine compartment to deliver the coolest air inlet temperatures possible. Cooler air carries more oxygen, which translates into a more intense explosion in the combustion chamber to create more horesepower and torque. But that?s only part of the power equation. Tuning the inlet pipe in length and diameter to match the engine?s resonance helps move more air to the cylinders (think of your engine as a big air pump), and no company on the market can tune an inlet as well as we can. We also monitor fuel trim correction factors and all OBDII sensors during R&D to eliminate leaning the engine out and/or throwing a check engine light.

Our Cold Air systems are dyno-proven and tested against the competition to create more useable power than any other system of their kind. Every AEM Cold Air induction system features the highest standards of construction and we are so confident in their fit and performance that we guarantee them for the life of your vehicle. All AEM Cold Air systems are either 50-state legal or pending (excluding ?Off Road? and ?Hybrid? systems), include a lifetime DRYFLOW Synthetic air filter and come with a limited lifetime warranty.

  • Outperforms every other Cold Air system on the market
  • Manufactured and assembled in the USA
  • 50-state legal or pending legality
  • Inlet constructed of lightweight aircraft aluminum and mandrel bent for maximum flow
  • Reinforced TIG-welded brackets and fittings deliver added durability
  • Utilizes a complete hardware kit with soft mounts for a guaranteed perfect fit
  • AEM?s lifetime DRYFLOW Synthetic air filter is 99.4% efficient, filters to one micron, and never needs filter oil!
  • Comprehensive installation instructions, decals and license plate frame included
  • Available powdercoated in red, blue or silver, or with a mirror-polished finish
  • Guaranteed for life

AEM Cold Air Intake System
C.A.S. HONDA CIVIC 1.8L L4 06-11
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Out of all the websites I've used to find my item, this was the lowest cost, and I'm so happy that I found them!  Keep up the great work guys!
Ordered on a Thursday evening and received my parts on Tuesday. Very quick but the website couldn't provide proper tracking info.
Had the product I wanted and at the lowest price. Thank you for the outstanding service!

This company offers profesional service at a very competitive price. The header collectors i ordered were not available at the big speed outlets. The fast shipping was also a plus. I would recomend Autoplicity to anyone who needs parts in a hurry !
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