K&N Air Filters.

[punisher]

I don't know why so many get bent out of shape about K&N air filters. They work perfectly fine for situations where filtering air is not an important consideration. I would go so far as to say that very few filters don't filter air like a K&N. I suppose you could match K&N's filtering ability with a piece of backdoor screen, or maybe some chicken wire fence, but I don't think it would seal very well in the air filter housing.

I suppose all of those oiled and dusted MAF sensors (as well as the FoMoCo SSMs) were just a figment of my imagination. Truth be told, I drank a bit (and may have done a few, very few, mind altering chemicals) during my decade+ as a performance tech, so you never know.

 

[ZeeOSix]

Originally Posted By: stchman
As I said before, if K&N air filters were so bad, then there would be hordes of tests from other manufacturers showing how bad they are.

All I hear is forum banter and one test done in 2004.

Also, where is this Chrysler TSB that states they will void engine warranty when a K&N is used on a Cummins engine?


If you don't want to believe comparative factual test data, then that's your choice. But seems you think just because no other manufactures are trying to smear the K&N brand that it's an indication that K&N filters are just as good or better than the others that the comparative test data clearly shows otherwise?

 

[stchman]

Originally Posted By: ZeeOSix
Originally Posted By: stchman
As I said before, if K&N air filters were so bad, then there would be hordes of tests from other manufacturers showing how bad they are.

All I hear is forum banter and one test done in 2004.

Also, where is this Chrysler TSB that states they will void engine warranty when a K&N is used on a Cummins engine?


If you don't want to believe comparative factual test data, then that's your choice. But seems you think just because no other manufactures are trying to smear the K&N brand that it's an indication that K&N filters are just as good or better than the others that the comparative test data clearly shows otherwise?

I just went back and re-read EVERY post in this thread, just to be sure I did not miss anything. I am a human and humans sometimes overlook things.

The only thing pointing to K&N air filters being bad is the Arlen Spicer test done in 2004. All the rest is forum hearsay. I have been using K&N air filters for over 10 years with no problems.

I was speaking to my friend who has K&N air filters in his 2010 Cobalt SS and his wife's 2009 CX-7. He recently did a UOA from Blackstone on both their vehicles. The UOAs came back with a silicon of 7 for his Cobalt and 8 for her CX-7. Those are good figures. Granted, neither of their vehicles are diesels nor do either of them operate their vehicles in really dust environments, but both their is a turbo and turbos do require more amounts of air.

With all this being said I plan on doing a UOA here very soon and will be paying particular attention to the silicon parameter. If the number is too high I will switch to a paper air filter and do another UOA later down the road. I am not one that readily accepts other peoples results and will get my own vehicle tested.

 

[Garak]

You have to look at the history of K&Ns. Even those who come down on them hardest here acknowledge they did have their time, as it were. In the days when air boxes weren't terribly efficient or good at protecting fitlers and when carbs were the norm and filter change intervals were too short, a K&N was the bees knees.

Other technologies have gone beyond that, though. Most people aren't stuck with changing air filters at short intervals any longer. So, the long life/low maintenance advantage of K&Ns is reduced. Part of that is due to better filter box design. That better design has also lead to better breathing. The K&N's advantage falls again. Fuel injection has displaced carbs.

I have a K&N laying around for my old F-150. I may very well use it. I'm not buying any for my G, though, when the [conservative] filter change interval is 24,000 km, and I can likely go much longer than that.

 

[y_p_w]

Originally Posted By: Garak
You have to look at the history of K&Ns. Even those who come down on them hardest here acknowledge they did have their time, as it were. In the days when air boxes weren't terribly efficient or good at protecting fitlers and when carbs were the norm and filter change intervals were too short, a K&N was the bees knees.

Other technologies have gone beyond that, though. Most people aren't stuck with changing air filters at short intervals any longer. So, the long life/low maintenance advantage of K&Ns is reduced. Part of that is due to better filter box design. That better design has also lead to better breathing. The K&N's advantage falls again. Fuel injection has displaced carbs.

I have a K&N laying around for my old F-150. I may very well use it. I'm not buying any for my G, though, when the [conservative] filter change interval is 24,000 km, and I can likely go much longer than that.

For the most part I'm thinking your right that modern air box design sort of makes any supposed gains of less restrictive filters meaningless or limited.

I remember some older edition of Car&Driver where they installed a K&N cone filter on an Integra and dyno'ed the thing. They did actually get slightly higher upper end power, but the lower end power actually went down a few HP.

Once I sort of got talked into getting one by a friend. I got a drop in filter for an '89 Integra along with a cleaning and reoiling kit. The issue I guess most people would have is cleaning and reoiling the thing just right without damaging the gauze. The loose gauze fibers are supposed to be integral to optimal filtration, but can be damaged. And how exactly did one know if it was reoiled just right. I got paranoid and figured I should reoil it often, which probably wasn't ideal. I think that filter is lying around somewhere, although the car's been sold for a long time.

 

[Garak]

Yes, and I'm talking about the drop in replacement for the factory air filters. Cold air intakes, of course, have different issues altogether, along with, at least theoretically, a different target market. The former is aimed more at people who are looking to reduce maintenance time and costs, along with a bit of marketing towards fuel economy and power. Of course, a CAI isn't going to save one much money.

 

[ZeeOSix]

Originally Posted By: stchman

The only thing pointing to K&N air filters being bad is the Arlen Spicer test done in 2004. All the rest is forum hearsay. I have been using K&N air filters for over 10 years with no problems.


I wouldn't call it "hearsay" ... I'd call it "experience with", just like you aren't going to believe anything unless you experience it yourself (you say so below).

When someone says they can see a definite difference in collected dirt on the inside of the intake tract downstream of the air filter with the K&N vs paper filters, then I take that as a real experience data point. You should try the same experiment and see if it's the same for you then.

Originally Posted By: stchman
I am not one that readily accepts other peoples results and will get my own vehicle tested.


Let us know what you come up with. Since you've admitted that you have used K&N filter for 10+ years, I think you don't want to find out this late in the game that they might have been less efficient at filtering than you care to accept.

 

[Jim Allen]

Originally Posted By: stchman

I just went back and re-read EVERY post in this thread, just to be sure I did not miss anything. I am a human and humans sometimes overlook things.

The only thing pointing to K&N air filters being bad is the Arlen Spicer test done in 2004. All the rest is forum hearsay. I have been using K&N air filters for over 10 years with no problems.


You just keep ignoring the advice you're given, I guess because you are desperate to justify your choice of 10 years past. Yes, much of the foaming-at-the-mouth you read about K&N is over the top. But the FACTS remain, they have a lower efficiency than most filters. All you have to do is look up efficiency specs. If you do, you will find the Spicer test to be accurate and accurate still. The only things that are dated might be due to changes that might have been made to some of the individual products that might change the exact readings. The tests themselves are done just as K&N or any other manufacturer would do them, so as long as you know whether a test is on fine or course dust, you can compare. I know you will ignore my detailed explanation, as you have ignored all the technical explanations before, but I intend to dog this until I get some acknowledgment from you, you quit, or we both die of old age.

By the way, the Spicer test is the ONLY wide ranging, independent industry standard (ISO5011) test that has EVER been done. You will find some shadetree tests done with talc and shop vacs but Arlen Spicer spend a lot of money doing what he did. That leaves you with doing some leg work to determine the actual efficiency of the filters you want to compare. Sometimes that means writing to the help lines of the company and asking for the specs.


Originally Posted By: stchman

I was speaking to my friend who has K&N air filters in his 2010 Cobalt SS and his wife's 2009 CX-7. He recently did a UOA from Blackstone on both their vehicles. The UOAs came back with a silicon of 7 for his Cobalt and 8 for her CX-7. Those are good figures. Granted, neither of their vehicles are diesels nor do either of them operate their vehicles in really dust environments, but both their is a turbo and turbos do require more amounts of air.


All that's great. Works for him. Glad to see the idea of environment has gotten thru.

Originally Posted By: stchman


With all this being said I plan on doing a UOA here very soon and will be paying particular attention to the silicon parameter. If the number is too high I will switch to a paper air filter and do another UOA later down the road. I am not one that readily accepts other peoples results and will get my own vehicle tested.


You need to bone up on oil analysis in general because one test is not the end-all-be all for this. It will give you a general indication but I suspect this is more your desire for justification than any real scientific curiosity.

You've heard a lot about why you shouldn't use a K&N. Why don't you tell us why you SHOULD use one? Why do YOU use one?

 

[Clevy]

Originally Posted By: stchman
Originally Posted By: ZeeOSix
Originally Posted By: stchman
As I said before, if K&N air filters were so bad, then there would be hordes of tests from other manufacturers showing how bad they are.

All I hear is forum banter and one test done in 2004.

Also, where is this Chrysler TSB that states they will void engine warranty when a K&N is used on a Cummins engine?


If you don't want to believe comparative factual test data, then that's your choice. But seems you think just because no other manufactures are trying to smear the K&N brand that it's an indication that K&N filters are just as good or better than the others that the comparative test data clearly shows otherwise?

I just went back and re-read EVERY post in this thread, just to be sure I did not miss anything. I am a human and humans sometimes overlook things.

The only thing pointing to K&N air filters being bad is the Arlen Spicer test done in 2004. All the rest is forum hearsay. I have been using K&N air filters for over 10 years with no problems.

I was speaking to my friend who has K&N air filters in his 2010 Cobalt SS and his wife's 2009 CX-7. He recently did a UOA from Blackstone on both their vehicles. The UOAs came back with a silicon of 7 for his Cobalt and 8 for her CX-7. Those are good figures. Granted, neither of their vehicles are diesels nor do either of them operate their vehicles in really dust environments, but both their is a turbo and turbos do require more amounts of air.

With all this being said I plan on doing a UOA here very soon and will be paying particular attention to the silicon parameter. If the number is too high I will switch to a paper air filter and do another UOA later down the road. I am not one that readily accepts other peoples results and will get my own vehicle tested.


Right on. So your "friend" operates a vehicle in conditions that one can call less than dusty and has a low silicon level in his oil sample.
Awesome. So under these seemingly ideal conditions an oiled gauze media filter keeps out the non existent dust.
Sounds like a job well done to me.

Jim Allen has forgotten more about filtration than most of us care to know. I consider him an authority on the subject and here at bitog there are a few guys I consider authorities and I try to absorb whatever I can when they do us the favour of posting their experience.
Do what you want with the wealth of info that he shares with us. I suggest taking advantage of it personally but I'm not one to waste what I consider valuable.

 

[Silk]

Originally Posted By: Jim Allen
Why don't you tell us why you SHOULD use one? Why do YOU use one?


I've often used K&N, usually because of a non standard situation - carburettor or engine change, sometime because of unavailable OE or aftermarket filters. I recently fitted a drop in K&N to my BMW motorcycle - partly because I got it a lot cheaper than genuine, and partly because I want to know one way or another if it will let more dirt through. I live in a not very dusty enviroment, and do 7,000km oil and filter changes. I'm not worried about oil getting through with a carburettor engine, but too much dust and I'll go back to OE.

 

[SteveSRT8]

Originally Posted By: stchman
That's ONE test and one test is not definitive and...
When I do a UOA soon I will be posting actual figures.


As noted, one test does not represent much, you need a series of UOA's to document any trends. Just one is like a snapshot, may not tell you much.

 

[Jim Allen]

Guys, I am hardly an"authority" though I do play one on Bitog (and appreciate the kind words Clevy). If I have any advantages over some of you it's access to information that comes from being able to talk to engineering people in the industry. Many times I have to keep those sources confidential because they certainly don't want to get involved in this sort of triviality. They are very matter-of-fact about these things... as would be normal for someone who deals in it every day... while we claw at each other over what they see as inconsequential details or incorrect premises or a complete lack of the facts.

My windmill tilting is simple: accurate (as possible) representation of the facts, regardless of marketing hype or brand names. Avoid and protest the over-the-top hysterics that come from half-truths, innuendo and bovine scatology. To be able to see the good and the bad, pros and cons. I fight the same urges to jump on the bandwagon as you do. Some people are so "my brand über alles" that they can't see the downsides to certain products, only the upsides. Or vice versa if it's a brand they hate. It isn't good when ego or self worth intrude to much into product selection. I really hate unwarranted and classles product bashing... like the guy urinating on the Fram filter.

My opinion of K&N? I think K&N is a great company. The products are generally well made. As has been said, they have a great R&D... I know because I've been there to see it. I wish they weren't invested so much into oiled cotton gauze but they are working in other areas too, especially since they now own AEM and have access to that technology and the brain trust behind it (John Concialdi). A great amount of "common knowledge" about K&N is incorrect (mainly the MAF thing) but the simple fact remains that the two ply filters are no better than average in efficiency and not particularly good at catching the fines. This is generally true of ALL similar oiled cotton gauze filters, regardless of manufacture. That may or may not be vital where you live but I ask why NOT run a higher efficiency filter if you can? For a stock engine, there is little to no power advantage to having a high flow filter in the stock housing. And if there is a 1-4 hp gain in it, which is rare (and that little amount of gain is within the margin for error for most chassis dynos anyway), in the higher rpm ranges mind you, how important is that day to day? Going to work., getting grocs, taking kids to soccer practice, etc. More dirt into your engine hurts you ALL the time while a few extra ponies only helps you that fraction percentage of time you are at WOT... and how important is that unless you race, haul moonshine or chase bad guys?

 

[ZeeOSix]

Originally Posted By: Jim Allen
More dirt into your engine hurts you ALL the time while a few extra ponies only helps you that fraction percentage of time you are at WOT... and how important is that unless you race, haul moonshine or chase bad guys?


Exactly, a better flowing air filter on a FI, computer controlled car only makes a difference at W-O-T.

 

[Garak]

Originally Posted By: Jim Allen
A great amount of "common knowledge" about K&N is incorrect (mainly the MAF thing)....

This should be repeated. Anyone who thinks you're biased against K&N should see that you've defended them on that issue many times.

 

[virginoil]

K & N overrated, designed for race use not street use.

 

[accent2012]

I've been using K&N in my car for over a year now and 15,000 miles later.

Any noticeable effects? No. Gas consumption appears the same.

Have I cleaned the filter yet? No.

Do I plan on cleaning it soon? No, I plan on cleaning when my car almost hits 80k miles. (50k miles running with the filter). I periodically check it and finger wipe the "clean" side of the air filter housing near the MAF and so far nothing, no greasy feeling, no dusty/dry feeling. So it must be doing its job, knock on wood.

I only bought it to cut back on buying a new filter every year and am quite comfortable with my experience with it so far.

I'd get an AEM since they use a synthetic media similar to the OEM filter, but designed to be used for longer intervals, but they don't make one for my car yet.

 

[Jim Allen]

accent, you are doing it just how it should be done! K&Ns have a great capacity and their so-so efficiency improves the dirtier they are.

I wont badmouth K&N's here but would point out that your annual filter change with the OE style was probably way overkill, Many of us here running restriction gauges (Filter Minder, Donaldson Informer, etc are doubling and tripling (if not more) the FCI by changing when the gauge indicates it's time.

When you do clean, treat that filter as you would a newborn baby to avoid decreasing the efficiency drastically by displacing cotton fibers. No matter what, every time you clean one, you lose a percent or so of initial efficiency.

 

[650NutKase]

OK not trying to start a fight, but I went ahead and ran 2 back to back UOA's using my K&N drop in. As you can see, the Si dropped significantly over the course of about 6000 miles. I'm not saying that K&N is just as good as the OEM but the numbers tell me that it's working well (as long as it's oiled properly and not completely clean). To be fair, I went ahead and bought an OEM air filter and put that in right after I changed the oil. Ill run another 2 UOA's to have a good comparison of K&N vs OEM.

link to UOA:
https://bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=3185935#Post3185935

 

[gaijinnv]

Originally Posted By: 2012AccentSE
OK not trying to start a fight, but I went ahead and ran 2 back to back UOA's using my K&N drop in. As you can see, the Si dropped significantly over the course of about 6000 miles. I'm not saying that K&N is just as good as the OEM but the numbers tell me that it's working well (as long as it's oiled properly and not completely clean). To be fair, I went ahead and bought an OEM air filter and put that in right after I changed the oil. Ill run another 2 UOA's to have a good comparison of K&N vs OEM.

link to UOA:
https://bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=3185935#Post3185935


You (and others) are assuming a direct relationship between Si levels in a UOA and air filter efficiency which has never been proven.

Run your vehicle for an OCI with no air filter at all and see what the Si level is - then we'll talk.

 

[901Memphis]

I would love to see a UOA with no air filter, that would be something.