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Old 08-05-2011, 06:12 PM   #1
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2012 Focus Custom Ram Air How-To

I've always been the type to have pride in the fact that I do my own work. And with that sometimes comes a better product. I knew I wanted an intake on my new Focus. I wanted a K&N filter. And I wanted it to be functional without being too "ricey", or have too much over-powering intake noise. So this is what I have been dreaming about the last few months.

Start by jumping on the net, or head to your local auto parts store, and order Gates part #22274. What you get is a 3" inside diameter, right angle heater hose. With very little trimming, it becomes the perfect fit! It runs about $37. I found mine for $23 on Amazon shipped!

While you're waiting for that to come in. Remove your airbox, along with the resonator you'll find under it bolted to the frame. I find it easiest to keep the MAF sensor attached to the box, and remove the hose clamp and wire harness to the MAF sensor.

Remove the front air dam plate by pushing it out back towards the engine bay. You can take your time to push each snap out of the way. Or just use a little extra force and it pops right out. I found this best. :)

I laid out a line across the center of each opening, and spaced out each hole I wanted to drill. Then over to drill the holes.

Finished. Of course you can drill your holes any way you like. I was going for a clean, not too obvious look while maintaining good airflow.

This is the area you want to run the hose through. It's a tight squeeze, so it will take some suggesting.

Should look like this once it's in place. Note, at this time the hose is uncut. What a nice fit eh! :)

Here's one of what she looks like from the top. (uncut)

From the first hose picture you'll notice it runs on a bit of an angle to the right. Measure back 2 inches, and cut a notch to act as a scoop. I used just a simple straight razor blade.

Here's a fun part. Remember that factory airbox we removed? Yeah well to buy one new it runs about $130. But that's ok, cause in a couple years people will be throwing them away when they buy their CAI. So you'll be able to pick on up down the road if you want to go back. But today we're going to drill a 3 1/2" hole in it! :) Get out your 3 1/2" hole saw, and cut a hole as close to the old resonator hole as possible. Always clean up your cut edges too! :)

Now put the box back in, and fully seat it in place. You want to adjust the hose so it feels relaxed. Then mark a line around the hose about a 1/4" from the bottom of the box. Remove the box, and cut the marked line.

After the hose is all cut. Reinstall your freshly drilled air dam plate, and then reinstall the hose. It may take a couple times of replacing the airbox to get the hose in the relaxed state again so you can make your bracket. I used 3/4" by 1/8" aluminum bar I get from the hardware store. While you're at the hardware store, pick up a nice stainless steel 3" hose clamp! My clamp looked like this when I was done. Depending on how you drilled your 3 1/2" hole in your airbox, yours may look different. You're going to use the hole that the resonator was using.

Now bolt your bracket in place, and install your hose clamp. BEAUTIFUL! Nice work! You're almost done!

Put your airbox back in, and adjust your hose to fit snugly in place.

Put your air filter back in, and bolt the air box cover back on. I chose to use a Outerwears pre-filter with this setup to prevent any water from getting in the engine. It also keeps bugs out of your pleats. Start her up and enjoy! Maybe roll her out on the driveway and give her a wash, cause you know you're going to want to go for a drive. :)

A little custom vinyl work to show off the Griffin Ram Air mod. :)

Now I know everyone is going to ask HOW DOES IT SOUND?!?!?! CLEAN! Not ricey at all! Not even as aggressive as a regular CAI. It has a very mellow throaty growl to it at WOT. However, which I like, it doesn't over power the engine note with LOUD intake noise. If you like LOUD intake noise, this won't cut it. If you like to hear your engine and intake compliment each other, this is it baby!


Also, I can hear people already complaining about dirt and water, etc etc. Easy fix. Of which I don't have pictured because it is still on order in the mail. Outerwears Pre-filters! With hydrophobic water shield. Either have one custom made for your filter, or hop on eBay and pick up one for an ATV and just slap it on the top side of your hose before it enters the box. I'll post pictures when I get mine in. And what about puddles and hydro-lock and all that CAI intake worries.... You're in luck. By leaving your existing factory pipes, they will act as your vacuum bypass. Aren't you smart! All your friends are going to love you! ;)

Hatch Nation #110
Debadge-and Drive Naked
Home of the Free Blacked Out Grille Mod, and Griffin Ram Air Mod.
Get you some!

Last edited by BLRich1; 03-02-2012 at 08:13 PM. Reason: added information
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