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Old 12-13-2003, 04:12 PM   #1
That Guy
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Question Cobb CAI Filter

Just bought it used. Took it apart and cleaned the filter today. But now I have to assemble it and put it on the car. Which way does the cone filter point? Pointy end towards the throttle body or towards the fender? Or does it matter? I looked on Cobb's website but they don't have a picture of an assembled one, just parts. Got pics of one installed on your car?

-Chris
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Old 12-13-2003, 04:26 PM   #2
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I believe it goes like a normal cone filter, pointy end pointing out, towards the fender. Just a guess tho.

AO
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Old 12-13-2003, 10:18 PM   #3
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Actually, it's the opposite.


The "point" should be facing towards the throttle body. Or, if you're standing in front of the car, the wide end should point to the left and the thin end should point to the right.

-Matt
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Old 12-14-2003, 12:55 PM   #4
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Quote:
Originally posted by Cobreth
Actually, it's the opposite.


The "point" should be facing towards the throttle body. Or, if you're standing in front of the car, the wide end should point to the left and the thin end should point to the right.

-Matt
really!?!/

uhh oh...installed it wrong; are you sure about that?
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Old 12-14-2003, 01:13 PM   #5
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I'm 95% sure. I'd go check, but I hit a deer 3 weeks ago and the car's still in the shop.

You can always call up COBB and they'll tell ya. They're real nice folk.



-Matt
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Old 12-14-2003, 09:38 PM   #6
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The cone "points" toward the TB. the open end is at the fender side.
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Old 12-14-2003, 10:01 PM   #7
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Quote:
Originally posted by blackbok
The cone "points" toward the TB. the open end is at the fender side.
hmm ive got the instructions with me and they say nothing either way. how did you guys make that determination?

edit: the reason im concerned is if you flip the filter orientation (so that the pointy end points towards the throttle body) it seems like you no longer have an 'air tight' filter section. the way i have it all air that enters the intake must go through the filter.

agree/disagree?
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Old 12-14-2003, 10:11 PM   #8
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Quote:
Originally posted by Jejunum
hmm ive got the instructions with me and they say nothing either way. how did you guys make that determination?

edit: the reason im concerned is if you flip the filter orientation (so that the pointy end points towards the throttle body) it seems like you no longer have an 'air tight' filter section. the way i have it all air that enters the intake must go through the filter.

agree/disagree?
I've never seen the air filter of this intake although someone here posted the exact same question as you. His was installed wrong as far as I remember. The concensus was that the 'wide-open' end goes to the fender while the 'pointed' end goes towards the throttle body.

I believe it's designed this way so that the velocity of the air increases as it's being sucked in towards the throttle body. If you have the 'larger opening' end facing the throttle body, then the airflow would actually slow down. You don't want that!
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Old 12-14-2003, 10:27 PM   #9
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Perhaps this will help you.



-Matt
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Old 12-14-2003, 10:36 PM   #10
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yah i guess according to that picture pointy end goes to the right; it still doesnt adress hte concern of unfiltered air entereing the throttle body does it?
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Old 12-15-2003, 12:23 AM   #11
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How is unfileted air getting into the throttle body?




-Matt
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Old 12-15-2003, 12:41 AM   #12
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Quote:
Originally posted by Cobreth
How is unfileted air getting into the throttle body?




-Matt
there isnt a complete seal between the filter housing and the filter is there? (if you orient the filter in the correct manner that is)

i guess i have to go switch it to see if there is; but just looking and assuming it doesnt seem like there is.
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Old 12-15-2003, 02:40 AM   #13
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Quote:
Originally posted by Jejunum
there isnt a complete seal between the filter housing and the filter is there? (if you orient the filter in the correct manner that is)

i guess i have to go switch it to see if there is; but just looking and assuming it doesnt seem like there is.
What? Orientation wouldn't affect that. The whole intake is sealed.
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Old 12-15-2003, 04:14 AM   #14
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Quote:
Originally posted by Cobreth

Perhaps this will help you.
-Matt
Hello Matt,

Can you tell me approximately how long that filter is from one end to the other? Heck, if you know the width also, please post. I have two Maf equipped Subarus (see sidebar) that I'd like to use the PDM inline air filter on but that filter with the Maf housing makes for a long 'straight' part. The intake bend from the throttle body to the Maf housing may have to be a lot shorter than I thought in order for me to custom make an intake like I'd like too.

So, do you know the length of that PDM inline air filter (Cobb air filter)?

BTW: I'm still baffled as to how this air filter flow so well compared to an open element filter-intake. From everything that we are taught, it would seem all that filter in the housing of the PDM intake would hinder air-flow severely. Like sucking water through a sponge laid flat vs sucking water through a sponge all crumpled and folded up.
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Old 12-15-2003, 11:55 AM   #15
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I'm not sure the exact length and width, and I can't measure it right now because the car is still in the shop. My best guess would be that it's around 8 inches long and around 3 inches in width.


Hopefully someone else can measure theirs. If not, I'll be sure to measure mine as soon as I get my car back from the shop.



-Matt
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Old 12-15-2003, 02:00 PM   #16
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This is how mine is installed:


If I get a chance tonight (and can remember), maybe I'll try to measure the filter.

As you can see in the picture, there are small set screws on the fender side of the intake. When you open that up, the wide open end of the filter sits on a lip in there. I can't see how unfiltered air would get around that.
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Old 12-15-2003, 05:42 PM   #17
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Pointy end towards throttle body. It acts like a velocity stack. This is how I have it mounted. If air going around the edge of the filter canister bothers you, put a small bead of silicone around it.

This picture is from PRM site:

PRM Racing
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Old 12-16-2003, 08:51 AM   #18
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Kevin Thomas:
It was too freakin cold out last night to be screwing around with my intake. It's supposed to be close to 40 tonight so maybe I'll measure it later today. BTW, PRM makes the Cobb intake filter not PDM.
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Old 12-16-2003, 11:12 AM   #19
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Its fluid dynamics at work. The velocity stack slowly accelerates (relativly) air into the tube past the filter. Other filters are just square where the pipe meets the filter, and are essentially just a pipe end that needs to basically accelerate air immediatly. Comparing a stack to a pipe in terms of ability to flow air is comparing a flintlock to a modern military assult rifle.

The filtering ability of the PRM might be a bit less or more depending on what filter you are comparing to. Manufacturers like to find the worst possible product and lable it as "competitor".

The post with the picture and web site link is the correct source for the filter, PRM. The previous post was correcting a member who was using the wrong name in their posts.

Greg
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Old 12-16-2003, 12:12 PM   #20
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Quote:
Originally posted by bigdweeb
BTW, PRM makes the Cobb intake filter not PDM.
Oops! That was a typo! Thanks for clearing that up.
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