Hi guys,

I've had the ram air intake that exexpat introduced to many of us for some time now and I took it off to inspect it and it seems like it's been slightly burning... I attached a picture of an area where there's actually a hole in the filter. There are a couple of these on the filter.

Has this happened to any of you guys? I immediately reverted to the stock intake but I want the ram air back. I was thinking of trying the AEM DryFlow cone filter. Is it possible to fit this filter into the bottom half of the stock airbox to provide some insulation and protection?

Thanks,
Erik

 

Here's the pic

 

ez, based on the picture, it looks like the filter is rubbing up against something and that is what is causing the hole to be formed in the filter.

I am running the stock air box, but I am using the K&N filter in the box. Unless you have opened up the exhaust, opening up the intake is going to net you very little other than looks. If that is what you are after, then great. But, don't be looking for any performance gains.

 

That does look more like a rubbed hole rather than a burn. I haven't noticed anything on my intake (I have the same setup) but I haven't looked at it in a while.

Thermo, I didn't really notice a real gain in power, but I love the sound it makes enough that it was justified as soon as I drove it. Then after I got the Mina exhaust and took my resonator out the whole setup sounded so good that I never really thought about how much, if any, power it added.

 

My first AEM DryFlow got rubbed too, and it was a bit too long anyway and the end rubbed against the engine cover as well.

When I fitted a new one, I also fashioned a sort of heat shield out of fireproof alloy-foil thermal insulation mat. It blocks airflow from underneath the engine cover and also prevents the filter from rubbing against anything harmful.

 

thermo, i do have 3 inch piping, no resonator, and magnaflow mufflers. but i didn't do the intake for performance at all. not even looks. it's purely for sound! also, i haven't heard good things about K&N filters, i hear they aren't very good at actually filtering. do you trust them?

also, i assure all of you the filter is pretty blackened on the bottom side so it's probably some sort of combination of rubbing against something and burning up.

justink201, i agree with you. the sound is so worth it.

aonsaithya, where did you get that insulation mat and how exactly did you install it?

and for anyone who can answer: does anyone have experience cutting out a part from the stock airbox to fit the big 9 or 10 inch cone filter into the box? i feel that'd make the most sense.

 

Here's a screenshot from a youtube video i just found with some sort of insulation around the cone filter. this is exactly what i want! i've seen it on a few different cars. did mina gallery used to sell it? anyone have any info on this?

 

Nyces from the UK forum is behind the video that is indeed the Mina Gallery kit. Their first kit had some issues, then they revised it a few times, then took some time and released that which is apparently the 5th version.

Added a photo to the post, I apparently forgot it at first. It's still in my signature too though. The mat I used is Aluthermo Quattro. I cut the pieces to shape and made a few holes, and the engine cover mounting bracket mounting bolts go through them.

I tried to fit the larger AEM cone I had earlier (21-2039DK so 9" long), but it was far from fitting in the airbox. To give a sense, look at my current photo, the 9" long filter pressed against the engine cover on the left side of the cone. The current one is 21-2038DK, 8" long.

 

ez, I trust the K&N filters very much. The big issue that a lot of people have with them is that they over oil them and that leads to oil going up the intake and taking out the MAF Sensor, making the car run like hell. But, you properly oil them, they filter just as well as any other filter with less restriction. Please keep in mind that I am basing it on the fact that in order to be minimizing problems, you are needing to remove 2 main sources of contaminants. Obviously, you want to get ride of the sand grain size stuff and larger that can get into the intake and cause obvious problems. An old shirt over the end of the intake tube will do this for you. So, any filter you buy in the store will meet that. The other particles you are worried about are the 1 micron in size and smaller. These are of concern as they have the ability to get past the rings, into the oil and then they can get into bearings and whatnot, leading to additional wear over time. The problem with these is no filter you can buy will filter to this level.

With all this being said, I will admit that the K&N in the first 500 miles or so will let a little bit more through than a comparable paper filter. But, from 500 miles on, the K&N will filter better because all of the "large" holes (relatively speaking here) in the filter have already been filled since they were letting a majority of the air through and now you are getting the finer filtering without the pressure drop that a paper filter will cause.

How much do I trust K&N filters? Enough that I am willing to drive my full size truck through water deep enough to come up on to the hood with no special snorkel or other similar device on it as the filter will keep the water out of the intake. It also works great in very dusty environments like i run into when out 4x4ing that would clog a paper filter in no time flat.

 

"Yeah, AEM is a division or subsidiary of K&N. The box had a K&N shipping label on it. The "I like messing with stuff like this" was a large part of it. I do perform my due diligence before ponying up for things like this, though, and the AEM DryFlow was tested in 2007 against K&N's own oiled gauze filter, aFe's oiled gauze filter, aFe's Pro Dry S (dry non-oiled) filter, and an Airaid oiled gauze filter by an independent lab, Southwest Research Institute. The AEM performed best @ 99.47% efficient using ISO 5011 fine dust test procedures. But the AEM also was, as expected with the better filtration, slightly more restrictive on air flow than the others."
('09-'13) Just installed an AEM DryFlow engine air filter - Subaru Forester Owners Forum

The superior filtration is one of the two reasons I chose the AEM DryFlow, non-oiled being the second.