K & N Filters; pros and cons?

[HRP]

Since K&N air filters were negatively commented upon in the "Good Deal On Oil" thread, I'd appreciate a knowledgeable discourse on the pros and cons of the K & N air filters. My son, who sells commercial filters for a huge range of industrial applications thinks very highly of them and even provided me with one for my Reatta. I clean it regularly and have had no problems. Please provide some commentary and references; either positive or negative (rather than opinions and personal experiences).

Thanks,

HRP

[Ronnie]

If you don't want opinions or personal experiences it would seem you are looking for someone to do research on the subject for you. I would suggest you could do it just as easily on your own by using Google or Yahoo.

A forum such as this is by nature a place for people to express their opinions and relate their experiences. Why would you wish to exclude opinions and personal knowledge on a forum?

[HRP]

Ronnie posted:

<span style="font-style: italic">"A forum such as this is by nature a place for people to express their opinions and relate their experiences. Why would you wish to exclude opinions and personal knowledge on a forum?"</span>

Personal opinions and experiences vary widely on about everything including K & N filters. Comments posted upon on-line forums frequently arrive at no general consenus. An example is whether or not K & N air filters filter well, increase performance and/or milage or the opposite. I was hoping someone was aware of definitive reviews, discussions, and comparisons with air filters, including K & N's, as, for example, there are for oil filters; the reference to which was, I believe, posted on this forum recently.

[jonlabree]

Look here for your K&N filter

http://www.bobistheoilguy.com/airfilter/airtest3.htm

[HRP]

Ronnie,

Thanks for the link. It also was not definitively conclusive:

<span style="font-style: italic">"Really, it is up to each individual to decide. The poorer flowing filters, remove more particles, and the better flowing filters remove less particles."</span>

Makes you wonder how our old "oil bath" filters compare. I guess I'll have to keep looking for the final answer. On the other hand, many of our auto manufacturers now are giving 80 to 100k and even lifetime powertrain warranties using "stock" filters. Maybe air filter quality isn't as important as we think it is.

[Richard S]

There have been lots of back-yard experiments done with oil bath filters vs. paper, as well as various free flow intakes. The conclusion reached by most of these experiments is that oil bath filters might offer a slight improvement in performance at 90+mph. Few of the replacement air flow systems improve performance because "turbulence", being the manner or quality of the air delivered to the plenum is just as, or more important than raw air speed. In this regard, the engineers at GM with their wind tunnels, sophisticated software, dynos, and test tracks have decided advantage over the aftermarket folks.

[KDirk]

Ok,

Might as well chime in here. I put a K&N in my 95 Deville (4.9L PFI) a couple of years back now. I have maintained it as directed and have this to say:

It filters the air, and that's about it.

Now, I didn't dyno test the car or any such fanciness (it's a Deville, not a hot rod) so I can not make any data-backed claims on it's potential effect on horsepower or fuel economy but there was no perceptible difference in the way the engine ran after the change from a stock paper filter.

Than again, this is the typical GM rectangle filter, and it seems that more might be gained with a custom intake and conical filter.

Personally, I have come to the conclusion that K&N's are overrated and overpriced [and yes this is opinion based upon conjecture, nothing more], but at the time I had a weak moment and decided to buy one. FWIW, I will probably not put one in my Reatta as I simply don't think there is much if anything to be gained in doing so. As well putting one in drops about another $50 into to the bottomless pit of vehicle maintenance.

Of note is that this same discussion has erupted from time to time on the Cadillac owners forum with no satisfactory resolution. My take is that this is all marketing magic, and some people will bite, some won't.

I am a brutally cynical guy so I am inclined to dismiss most marketing claims as nothing but an attempt to sell more product than one's competitor. If it fulfills that purpose, good for them. YMMV.

KDirk

[Guest imported_barra]

A few years ago, Mr. Padgett posted a comparison of air filters. I do not remember the title under which it was posted. The net result was that the GM Delco filter did the best job filtering the smallest air particles.

[padgett]

If I did a comparison it would have been of stock and replacement since I do not have a K&N. What I remember is not liking the Fram and thinking the Purolator was pretty good.

There are a number of people who swear by K&Ns. The only potential problem that I have heard of is that over-oiling can cause problems with the MAF sensor.

[Guest Ranger]

Funny, HRP is quoting his son who sels commercial filters, he's quoting on his son's opinion but doesn't want anyone else's.

Reminds me of a grad Stats. course I took long ago. The advertising slogan "9 out of 10 doctors interviewed recommend Bayer aspirin", well the 10 docs interviewed were on a cruise payed for by Bayer.

You don't suppose HRP's son was...................no, never mind, we don't need opinions here.

Jim

[Reatta45]

If the air really needs to be clean, you will find a paper type element up stream. Automotive, medical, any lab environment…

There are a lot of filtering media available, in the CFM requirement needed for street driving, a good paper, one time use, is the most economical and best application.

C&N was marketed to sell… that dose not mean it is necessarily something to buy. KennyV.