Roush Cold Air Intake Kit Focus ST 2013-2017

Roush: 421609
MSRP: $315.99
CJ's Low Price:
1490227200 4254
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Roush Cold Air Intake Kit Focus ST 2013-2017
Roush Cold Air Intake Kit Focus ST 2013-2017 Roush Cold Air Intake Kit Focus ST 2013-2017 Roush Cold Air Intake Kit Focus ST 2013-2017 Roush Cold Air Intake Kit Focus ST 2013-2017 Roush Cold Air Intake Kit Focus ST 2013-2017 Roush Cold Air Intake Kit Focus ST 2013-2017 Roush Cold Air Intake Kit Focus ST 2013-2017 Roush Cold Air Intake Kit Focus ST 2013-2017 Play Roush Cold Air Intake Kit Focus ST 2013-2017 Video 1

Product Description

Roush Cold Air Intake Kit for all 2013, 2014, 2015, 2016 and 2017 Focus STs.

Add some horsepower to your Focus with the addition of a 421609 Roush cold air intake. Along with increased horsepower is enhanced sound from the blow-off valve. No drilling or cutting is required. This simple bolt-on intake maintains the factory PCV connection and utilizes factory PCM calibration.

Features 3" aircraft-grade aluminum induction tube with black texture finish for maximum air flow. A high flow air filter element is re-usable and washable. Premium silicone couplers have reinforced, weaved fibers for superior sealability. The 421609 system is topped off with a custom Roush stamped air box with air-tight hood foam seal.

- Premium high flow air filter with clamp
- One silicone coupler
- One aluminum induction tube
- Two mounting clamps
- Airbox tray with EPDM foam hood seal
- Instruction manual

*Not approved for use in California or states that require a California EO#.

Order a Roush Cold Air Intake Kit for your 2013, 2014, 2015, 2016 or 2017 Focus ST from CJ Pony Parts today!


Installation Instructions

Mustang Installation

Product Reviews

Write a review
Roush Cold Air Intake Kit Focus ST 2013-2017 is rated 4.8 out of 5 by 34.
Rated 5 out of 5 by from Awesome Intake After bouncing around on many different intakes, I finally decided on this one. Most of the intakes I researched all used the same Green Filter (which is fantastic), so it came down to price and features. I'll admit, I chose the Roush because the open air box is aesthetically pleasing, and the price is superb! The parts are all very high quality, and installation was a breeze (with the proper tools). The suction and blowoff sounds are phenominal thanks to the filter. You also get a nice gurgling when you let off the throttle without engaging the turbo. Finally, you can definitely feel an excellent increase in throttle response. Overall, great product and I would recommend it to any ST friends.
Date published: 2015-01-29
Rated 5 out of 5 by from Roush COI for Focus ST I've had this on now for a couple of weeks. Minimal performance gains, but I like that I can hear my turbo now. I'm using this as a starting point for future upgrades. Installation was pretty easy. It took me just over one hour and I could probably do it again in under 45 minutes.
Date published: 2015-06-16
Rated 5 out of 5 by from Excellent Product ! I just installed this intake on my 2015 ST. I installed the shifter base bushing and the short throw shifter kit a the same time. The entire process took about tow hours. It is like driving a different car. Installation was pretty easy with proper tools and experience. Seem to have some minimal HP gains but increased throttle response. I am installing the Accessport V3 today. I have also installed he turbosmart blowback valve. I highly recommend this CAI from Roush.
Date published: 2015-08-14
Rated 5 out of 5 by from Sounds like a whole different monster! I installed the system today - not bad, except for the lower hose clamp in the air inlet - after dropping my screwdriver into the engine bay and shredding my arm trying to get it out. otherwise fairly simple install - definitely need a 1/4 swivel 8mm socket to remove the hose clamps. Sounds like I awoke some god of thunder - growls at low rpm and really moves some air volume on acceleration - can't wait to really put it to the test and check my fuel mileage
Date published: 2015-07-03
Rated 5 out of 5 by from Looks great I have had this on for about a month. Gas mileage has not changed but the performance and sound has. The car seams to respond quicker. And it looks really cool.
Date published: 2015-02-09
Rated 5 out of 5 by from looks and sounds awsome Easy to install and looks the best under the hood ! No better name brand under a ford hood then roush.
Date published: 2015-03-24
Rated 5 out of 5 by from Amazing Sound The sound that comes from this kit is amazing. The spooling noise is perfect and it gives you a great hiss on gear change alot of people have asked if its a dump valve fitted. Check out my vid of it here
Date published: 2016-09-27
Rated 5 out of 5 by from Awesome product! Bought earlier this month. Installation was decent had two hiccups. Difficult to get the coupling on the air inlet tube (nothing a little grease couldnt help with) and the attachment point closest to the airbox seemed to be distorted slightly (Didnt light up great and was slightly tilted). Nothing major though. It sounds good, looks good, feels good.
Date published: 2015-03-18
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Product Questions

Is the Roush air filter an open end air filter?

Asked by: Nickalaj21
It is exactly as shown in the image.
Answered by: CJPP Dave
Date published: 2017-02-07

Will this work on 2017 model?

Asked by: Caleb
Both Roush and CJ's have not had a chance to test fit this on a '17 yet to confirm fitment. With that being said, I am not aware of any major changes on the '17 model that would keep this from working though.
Answered by: CJPP Dave
Date published: 2017-01-26

Can i install this in a 2013 focus se

Asked by: Catchemall
Answered by: CJPP Dave
Date published: 2016-07-18

would this fit a 2015 Australian focus ST

Asked by: jacob101
Unfortunately I cannot accurately answer your question. Without the vendor supplying any information regarding fitment for non-US Spec vehicles and CJ's not having a vehicle to test parts on, we cannot confirm this part working on your vehicle at this time.
Answered by: CJPP Dave
Date published: 2016-05-10

This roush intake isnt street legal in California, can i still purchase it

Asked by: stguy
You can still purchase this intake if you live in California. However, you will not pass vehicle inspection that California requires. It's up to you if you want to deal with failing California inspections.
Answered by: Rascal
Date published: 2016-04-08

I like the look and reviews for this CAI, but want to know if the COBB CAI pairs better with my V3 AP (purchased and tuned through Mountune) and the MBRP XP Cat back I recently installed. What's your professional opinion? 

Asked by: ScottyD
COBB parts always pair the best with the COBB accessport.
Answered by: CJPP Dave
Date published: 2016-03-14

What hp gains can be expected for a 16 Focus ST?

Asked by: wooddogg
There will definitely be a slight increase in horsepower And torque, but overall gains can and will be determined by other modifications that you may have, And whether or not you have a tune on your Focus ST.
Answered by: CJPP Dave
Date published: 2017-01-26

Is this upgrade California smog legal?

Asked by: f00tball_player
Answered by: CJPP Dave
Date published: 2016-12-29
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Product Video

Roush Cold Air Intake Kit Focus ST 2013-2017 Video Transcript
By Bill Tumas: The Focus ST makes great power stock, but like any true hot ride, we're always looking for ways to make some horsepower. Whether your car is naturally aspirated, super charged or turbo charged like our Focus, a good cold air kit is one of the easiest ways to add horsepower. Today, we're going to install this Roush Performance cold air kit on our 2013 Focus ST.

The Roush kit comes with everything necessary to install on your Focus including this inlet tube which comes in black. We actually powder-coated ours white to match our car. Comes with the silicone couplers, hose clamps, seal, a new box and a reusable filter. For this installation, you need a quarter inch ratchet, 7 mm socket, 8mm socket, 12mm deep socket, extension, flat head screwdriver, flashlight and scissors.

Our Roush cold air kit is going to replace our air box lid with a high flow lid, we'll replace this tube here as well while still keeping the stock mass air meter. The first step is to remove our engine cover. Simply pull straight up and put it aside. The air box lid is held in place by these four bolts here, so we'll remove our stock paper filter, and we're going to remove the factory clamp for the rubber boot here and the other one on the side.

I'll separate it from the cam cover and remove. Now we can remove these two mounting bolts here from the cam cover to get the rest inlet tube off. This is your normal 8mm, but for this we're going to need a deep socket and you want to make sure you keep this, because this is actually one of the mounting points for your factory engine cover and you will reuse it.

I'm going to disconnect the PCV from the back of the tube. Simply squeeze them together and push backward. The last plan for removing the stock air tube is kind of hard to see but it's down behind the cam cover, it's the same size as the other one. Simply remove it and pull the whole tube off.

You want to remove the steel inserts from the factory air tube, you're going to use two of them in your new Roush. Simply push up on the metal insert, pull the insert out and then remove the washer. Now, we'll install the inserts we just removed on to our Roush inlet tube. Now, we'll install the coupler onto the tube here, and install the supplied clamp.

Now, we'll connect our cold air kit to the factory lower tube on the turbo, this will be the hardest part of the installation, since it's so far down the engine bay. You'll notice we actually put some towels on top of our engine to protect our powder kit, we do the same thing with the stock paint as well.

I'm going to tighten the clamp up by hand just to get it to hold before going there and tighten it down for good. We'll reach behind and connect our PCV to the inlet, pull our towels out, now connect to our meter, now tighten down the factory clamp. You want to install the Roush supply washer underneath this and then reinstall the factory bolt.

We'll reinstall the factory mounting stub for our cover. We'll reinstall the bolt to the throttle body, we'll then install our new filter. Now, we'll install the factory screws from our factory lid into our new Roush open lid and tighten everything down. Now, install the seal which snaps into place. Now, cut off the excess. Our last step is to reinstall our engine cover and our installation is finished.

A Roush cold air kit is definitely a lot less restrictive, so it should pick up some horsepower without any additional tuning necessary. Installation should only take you around an hour and you'll be back on the road in no time.