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Part number: 21-451B
Call For Availability: 800-299-1028
Product Details
AEM 21-451B Cold Air Intake System
Products specifications
CARB EO Number D-670
Color Blue
Filter Color Gray
Filter End Cap Finish Black
Notes Fits DOHC Zetec motors only.
Quantity Sold as a kit.
Sleeve Color Black
Tube Color Blue powdercoated
Tube Material Aluminum
Clamp Material Steel
Clamp Style Regular
Intake Pipe Color / Finish Blue
Clamps Included 5
Product Style AEM Cold Air Intake System
Replacement Filter 21-203DK
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 7 lb (3.2 kg)

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 horsepower 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 this tuning allows us to deliver the maximum power gains throughout the entire RPM range. 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 with the goal of creating 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.

  • Guaranteed for life
  • 50-state legal or pending legality - Excluding intake systems that are designated as Off-Road Use Only.
  • Manufactured and assembled in the USA
  • Engineered to produce maximum horsepower and torque
  • AEMs lifetime DRYFLOW Synthetic air filter is up to 99.52% efficient in FINE DUST testing, filters dirt as small as one micron, and never needs filter oil!
Reviews
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R


Borgeson 000940

I found Autoplicity during a price search on the Borgeson steering shaft for my truck. I had never heard of them, and was a bit skepticle. But after doing some research, found that Autoplicity has a good reputation on a Jeep forum I visit.

I decided to order, and I am impresed. Extremely fast shipping, I placed my order on Saturday, and its now Monday before noon. I am holding the new part!
D
Best price around. Great Communication. Fast shipping. What else can I ask for?
I have already purchased again from them.
C
Quick shipping and they had the fuel jugs I needed for the best prices thanks!

UPDATE: they were so good I made another order with them within a week.
T
Google searching produced this company as the lowest price on a set of spark plug wires.  I like to deal with eBay, but I decided to try it out.  Though the shipping was a bit more than Google estimated, it was still the lowest price!  The item shipped quickly and was perfect with plenty of communication.  Great seller!
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Fitment
Ford Focus
2004 Ford Focus ALL / LX / SE / SVT / ZTS / ZX3 / ZX5
2003 Ford Focus ALL / LX / SE / SVT / ZTS / ZTW / ZX3 / ZX5
2002 Ford Focus ALL / LX / S2 / SE / Street / SVT / ZTS / ZTW / ZX3 / ZX5
Return Policy
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