at what point will a factory size K&N airfilther become a restriction

blown96bird

Registered User
I am wondering at what point will the factory size air filther become a restriction using a K&N air filther? I know that the factory airfilther has 64 square inches of surface area. The cone filther I am planiing on using has a surface area of 140 square inches. I might be wrong but I have cauclulated that my car is pulling around 700 cfm under wot.
 
Surface area?

blown96bird said:
I know that the factory airfilther has 64 square inches of surface area.
How are you measureing that? Simple length x height? OR actually measureing the surface area of the pleats?

I ran 14.250 @ 97.6 with a K&N panel. What mods you got?

68COUGAR
 
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just a word to the wise. DON'T oil that K&N! It's becoming widely known that the oil will contaminate and kill a MAF sensor.
 
MAF Genocide?

RBH Racing said:
DON'T oil that K&N! It's becoming widely known that the oil will contaminate and kill a MAF sensor.
ALL K&N filters are oil impregnated. Most live many years and play nicely with the MAF.

I believe what you are Attempting to say, is not to OVER oil the gauze filter, after it is washed. That is where people get into trouble, buy using to much K&N oil. Reapplying the CORRECT amount of oil will not "kill" or hurt the MAF.

68COUGAR
 
I measured the filther from the flat area not the indivual pleats. I recently cleaned my pannel. The center looked like It had mud in the center it was so dirty. I oiled my filther and then pulled air through it for 30 minuites on a box fan then wiped the wire mesh with a dry cloth to remove any extra oil. I normaly clean the maf every 2 months with alcohol.
 
No, I meant what I said man. There are several tests that you can find on the net showing this, let alone the numerous TSB's and Warranty denile sheets that you can find. They are originally oiled from the factory, and what is being found is that many are sitting on shelves long enough to allow the oil to be absorbed by the boxes. This leaves customers thinking they are fine. Even the prescribed oiling can do it, trust me I've seen it happen on cars other than the SC's. K&N's are great but use them at your own risk on MAF cars.
 
That's amazing. There are a LARGE number of people here using K&N and/or similar reusable oiled air filters and no one has a any real problems so far. :rolleyes:

I do recall reading where a couple people who may have over oiled their filters had an issue with the MAF but it was quickly solved by simply CLEANING the MAF. No real big deal. Besides our cars, I know of literally HUNDREDS of people using K&N or similar filters located just before the MAF and have never heard of ANY of them hurting the MAF.
RBH Racing said:
There are several tests that you can find on the net showing this, let alone the numerous TSB's and Warranty denile sheets that you can find.
Please provide some links to this information. I am sure I am not the only one here that would like to see some credible information/data that supports what you say. I guess anything is possible, but I would have to see it to believe it as, like I said, I have NEVER heard before that the use of a K&N filter will...
RBH Racing said:
contaminate and kill a MAF sensor.

Tracy
 
I think the main point of all this is to keep an eye on the MAF....

I put a K&N cone filter on mine and knew about the oiling problem....

When she started to loose some performance, I cleaned the MAF with parts cleaner and it seemed to help.....

I have had the MAF in my Subaru completely saturated with oil numerous times (don't ask, long story, but pretty interesting) and it still works.....
 
XR7inWI said:
I do recall reading where a couple people who may have over oiled their filters had an issue with the MAF but it was quickly solved by simply CLEANING the MAF. No real big deal. Besides our cars, I know of literally HUNDREDS of people using K&N or similar filters located just before the MAF and have never heard of ANY of them hurting the MAF.

Agreed. This has been argued over and over again. The only real problems occurring with K&N's is when people over-oil their filters. Under normal cleaning conditions, and using the proper amount of oil, there should be no problems, other than cleaning your MAF from time to time, which you really should be doing anyway as part of regular maintenance.

If the oil really bothers you, just stick with a regular Motorcraft paper filter. You'll have to replace it often, but it will do the same job. Blown96, unless you're trying to figure this out for curiosity's sake, I wouldn't worry about it. You're not going to be able to gain much in the way of less restriction via the filter, short of removing it altogether.
 
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I have found out what the airflow rate per square inch. It is 6.25 to 6.82 cfm per square inch at 1.5 inches of water. using the 6.82 square inch formula the factory size K&N is good for about 435 cfm. It might be a good possiability that I have a restriction. BTW how much airflow can a 3 inch pipe flow?
 
How would the factory treated filters leak through the sealed celophane (sp?) that the K&Ns come in???
 
blown96bird said:
I am wondering at what point will the factory size air filther become a restriction using a K&N air filther? I know that the factory airfilther has 64 square inches of surface area. The cone filther I am planiing on using has a surface area of 140 square inches. I might be wrong but I have cauclulated that my car is pulling around 700 cfm under wot.
All of them will have the same CFM rating, one will just be bigger than the other. To avoid all confusion, just get some 3" exhaust pipe and a cone filter, then be done with it. Take the air silencer out too.
 
I am using mandrel bent 3.5 inch tubing for the air inlet to the throttlebody. I custom made my air intake tube.
 
sizemoremk said:
How would the factory treated filters leak through the sealed celophane (sp?) that the K&Ns come in???


That's EXACTLY what I was wondering. I specifically remember removing my K&N cone filter from a plastic bag inside the cardboard box. I doubt seriously that very much oil was absorbed by that clear plastic. :rolleyes:

Tracy
 
Well seems I'm not alone in understanding the threat of contamination. As far as the plastic bag they come in, it may be hard to believe but it's not impermiable to the oil, and I have been buying K&N's for near 10 years now I think. I do remember the days when they did not come in plastic bags.

Of course what would I know. We have been racing in the Outlaw class for over 15 years now running in the 7.80's-7.60's (in our Camaro, not the SC) with around 1,100hp that we build ourselves.

I was only stating the facts and making a general warning that may save this guy a lot of headaches. If your big on cleaning your MAF, then it may well never bother you. Most people don't even know where it is........
 
RBH Racing said:
Most people don't even know where it is........

Hahaha, ain't that the truth.

And I apologize, I wasn't questioning your experience. You obviously know better than I would.

Doesn't not oiling the filter decrease it's efficiency though?
 
The K&N air filter is constructed of i think its some kind of cotton. The oil is there to HELP trap dirt and all that icky stuff you dont want in your motor. So if you do not oil you K&N filter or any other kind of re-useable air filter, then you arent getting the air coming into the motor clean enough. On the newer models, the MAF sensor wires heat up to like i think its 1000 degrees F. when you shut the motor off to get off all the contaminats (sp) and what not off of it, not really sure if the MAF on the SC does that or not. Moral of this story, if your not going to oil you K&N, then dont bother putting one it.


Derek
 
lets quit hijacking the thread. I have found out that a K&N can flow between 6.25 and 6.75 cfm per square inch at 1.5 inches of water. That meens that the factory size K&N airfilther is good for about 435 cfm any more and it will create a snifgant vacuum.
 
I have had K&N panel on my 5.0 Mustang and my SC for years with no MAF problems and when you unfold the pleats on a K&N panel I suspect you will find 200 sq in of element which should be good for 1200 cfm. Charles Warner measured only .25 psi drop with a K&N panel and 0 drop with a cone filter. http://www.sccoa.com/articles/cwintake.php
catch you later, Bob.
 
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