Roush Cold Air Intake Kit for all 2013, 2014, 2015 and 2016 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 or 2016 Focus ST from CJ Pony Parts today!
Product ReviewsWrite a review
would this fit a 2015 Australian focus ST
This roush intake isnt street legal in California, can i still purchase it
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?
What hp gains can be expected for a 16 Focus ST?
Is this upgrade California smog legal?
I read from you guys that this doesn't fit a 2016 model. What CAI does fit the 2016 FoST
I'm going to be purchasing a 2016 focus st, will this intake and the Roush cat back exhaust fit the 2016 model?
Will this in any way void the factory warranty?
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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.