Tell me about K&N Filters

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Overland-Indiana

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Are the K&N air filters worth the cash? I have never used them. I know some people swear by them but, do they really increase horsepower, throttle response or MPG?
 

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The new thing in the car world is to be completely against K&N and all wet oiled filters. Their argument is the oiled filters flow less, cost more and coat/ruin Mass air flow sensors. I've been buying K&N for 25 years and I've never had any of those issues. I have on a couple occasions seen them over oiled out of the box and I've never seen a user not over oil them after they serviced them, themselves.

Another argument against most CAI Kits is that many draw in Hot air from the engine. That could be true, again I've never noticed a difference and all my years on Dyno's never yielded anything substantial from any CAI kit I've used or tuned. (Also, dyno's aren't real world and I get that.) :0)

These days, I usually stick with a Drop in replacement filter; either Wix's Dry premium or the K&N. Wix are a fraction of the K&N cost but they're perishable.

My F-150 has a K&N but it's also factory routed through the fender. My wife's '16 Maxima and old BMW have and had Wix. My race car had a K&N.

MPG and throttle response are both big selling features of expensive CAI kits and results are usually predicted by the Driver's habits. As a kid, I once had a CAI on a econo car and my MPG went down because I was driving by sound. Which usually made me drive more aggressively. A lot of CAI kits do away with the sound chamber baffles that lessen the turbulence and sound from the incoming air.

All points are valid fore and against, lol. I just buy what I buy. :)
 
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TreXTerra

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I ran K&N in my motorcycle and SUV for a few years. I switched back to paper filters because I noticed a lot of oily grime on the wrong side of the intake. A K&N is supposed to flow better than a paper filter, but there are only two ways I know of to do that: a larger filter area or a more open filter that can move higher volumes in the same amount of time and space. Since a new drop-in filter isn't any larger that must mean it is more open. That means more grit makes it past the filter and into the engine - generally speaking, that's bad for engine life. I am getting the same MPG and performance by keeping a clean paper filter in the car as I was with the K&N, but I don't have oil and grit in my I take anymore.
 

Overland-Indiana

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I ran K&N in my motorcycle and SUV for a few years. I switched back to paper filters because I noticed a lot of oily grime on the wrong side of the intake. A K&N is supposed to flow better than a paper filter, but there are only two ways I know of to do that: a larger filter area or a more open filter that can move higher volumes in the same amount of time and space. Since a new drop-in filter isn't any larger that must mean it is more open. That means more grit makes it past the filter and into the engine - generally speaking, that's bad for engine life. I am getting the same MPG and performance by keeping a clean paper filter in the car as I was with the K&N, but I don't have oil and grit in my I take anymore.
Good point. I never thought about how th oil could affect that. I was curious because people swear by them
 

Overland-Indiana

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After more research i think i'll just stick with paper filters. There is not enough evidence to make me want to switch over.
 

Overland-Indiana

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Plus i don't want to mess with cleaning and oiling it, just wanna toss it and buy a new one.
 

hardtrailz

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Here are my real life pics and praise of the Green Filter I use. http://gmtnation.com/forums/threads/green-filter-experience.155/ It is an oiled filter, but I use little oil and make sure it is dry prior to install. I won't use anything else on something I drive off pavement.

On-Topic: A K/N lets in a ton more dirt. The Green Filter, I use is not in these tests, but it does show how much the K/N lets through in real testing.

One of my buddy's post from another forum on this topic
" http://www.dieselplace.com/forum/sho...d.php?t=117009

http://www.billswebspace.com/AirFilterTest.htm

It's the "spicer air filter test", but it's down right now... That's also why the pictures on billswebspace aren't showing up...

http://home.usadatanet.net/~jbplock/ISO5011/SPICER.htm

The moral of the story off the top of my head is, the K&N lets past 18x more "dirt" in the "dirt test", and in the fine dust test, the AC Delco catches 99.97% of the fine dust, and the K&N catches right around 96%... (4% / .03% = 133x) "
 
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pl626

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Paper filters for dirt roads, K&N on pavement...


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