Written by Mustangworld.

Lots of pics, I hope your on the net at 28.8 or faster.

Pic of K & N Boxes...3.8L K & N. Part E-0940
K & N Air filter and cleaning kit . Filter $39,
Cleaning Kit $10. This is what comes in the box.

Ok, so you want a little extra HP for under $50 ? Purchase a K & N Air Filter ! There are other performance filter manufacturers out there all using the same basic principle to improve air flow...using cotton instead of paper for air filtration. But remember, cotton alone will not work, you also need a slight "film" of oil on the cotton to ensure the cotton grabs all the dirt and grime. This oil gives the cotton a reddish / orange look. Don't expect to "feel" a great increase in HP. Expect a stang that sounds a bit louder at high rpms, revs up and down a little faster, has a little more pickup coming out of turns and breathes easier. The HP gain depends on your mods, but on a stock stang, I'd say from 2 - 4 HP. The 3.8L K&N air filter is available at Chief Auto performance shops. They had it in stock.

Another reason to buy a cotton filter is the ability to wash them and re-use them. Some of us here live on dirt roads and we have to drive several miles on dirt to get to our houses in the hills (this is where we also "rally race" our stangs, like a bunch of Pikes Peak racers) the air filters get real dirty, real quick. Without a K & N Air filter, we'd have to buy 2 filters a year just to maintain a clean intake. A cotton filter can be washed and re-washed to work like new, for the life of your stang.

You can also purchase the K & N "Filter Charger" system for $89. This is a system (includes a metal bracket and air filter) that completely replaces your air box and runs the filter element completely exposed to maximize air intake. Keep in mind that in some situations, an open air element may get dirty faster than one that is inside a filter box. We just went with the regular $39 air filter element alone, a stock air filter replacement, because this project stang will see dirt road action almost every day. We left our stock air box in place, but still removed the air silencer.

Get the right part no. for your Stang. This particular application was: 1996 Mustang 3.8L V6 K & N Filter Part E-0940. Cleaning kit 99-5000.


1. Here's the 3.8L Air filter box. We've already removed the air silencer, so replacing the air filter is a piece of cake. With the air silencer in place, it's more difficult because the air silencer goes into the fender well about 10" or so. We only have to remove one bolt and a latch, I'm un-bolting it here. Un-bolt the air box
2. Now we must un-latch the 2 latches that hold the air box to the MAS air assembly. One's on top, one's on the side. un-latch the air box
3. Next we'll pull the air box from the MAS air assembly. Notice on the 3.8L there is a plastic TAB at the bottom (where my pinky finger is) this means that we'll have to lift up and let the air box drop out of this TAB before we can pull it off. Remove Air Box.
4. Now that the air box is out, remove the old filter. Your new K & N comes pre-oiled, so all we need to do is drop it in place. Also notice one of the two rubber grommets at the bottom of the air filter, we'll need to line these up when we re-install the air box. Drop in the K & N.
5. Now just re-install the air box taking into account the TAB and grommets we showed in the above steps. Re-latch the 2 latches. Then re-bolt the air box with the one bolt at the top and you're done! Re-latch air box
6. The kit comes with a sticker that says "STOP YOU FOOL ! Don't throw away my air filter, I can re-use it !" It's wise to stick it some place visible. We put ours on the metal space to the left of the radiator, just next to the hood support on the passenger side. Stickers don't stick to well to the air box itself. This is in case you take your Stang in for service, you don't want the dudes to trash your filter. STOP! Don't Throw away my K & N!
7. This is the $10 Cleaning kit that you use to clean out your filter. When it gets dirty, you spray it down with this cleaner, soak it for 15 minutes, hose it down, dry it, then re-oil it with this oil. Your back in business. Every K & N filter comes with a million mile warranty. You can wash your filter like 10 times with this kit. Cleaning Kit.

Hey....yer totally done dede!....til next time.... see ya on the street !

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