K&N airfilters

scramble this

Umm.. Where am I?
Location
West Jordan, UT
I would never put one on my car and heres why. i am a technician for a company that make 95% of their cars with a turbo, and the biggest problem we have seen with kn is in a turbo. on the intake side of the turbo the blades form a knife like edge (which is not at all normal) due to increased particulate travel. this has caused a few to fail (noise or reduced perfomance usually). given that, i would not put one on my car cause it is a turbo and that to me is evidence of more dirt where it shouldnt be, not to mention any engine repair on a foreign car is not cheap and i want it to run forever. whether its people not oiling correctly or whatever, im not taking the chance.
 

onetuff76

Guard Rail Tester
Location
Lehi
DeadEye J said:
I run a K&N on my quad. Every time I clean the filter, there is dirt in the intake side of the carb. And not a small amount either. I know it allows more dirt into the motor, but it is a heavily modified 2 stroke that flows alot of air. It also happens to be about $150 and a few hours work to rebuild the top end, so I'm not too worried about it.

My personal opinion about K&N's is that they flow like crazy, but have a marginal ability to filter out fine dust. If you aren't worried about engine longevity, and use a modified engine at high RPM's consistently than this is definately the filter for you.

I ran one in my Bronco II for a few years, and just like the quad I would find dirt inside the air intake tube. After switching back to FRAM stuff, there was alot less dirt getting past the filter. I will never again run a K&N filter on a daily driver, because 1-5 HP at redline is not worth sucking dirt into my motor. Paying $50 or more to shorten the life of my engine and only getting marginal performance gains sounds like a rather foolish idea.

Jared

you have to oil it again after you clean it :D
 

twigboy

Registered User
scramble this said:
i would not put one on my car cause it is a turbo and that to me is evidence of more dirt where it shouldnt be, not to mention any engine repair on a foreign car is not cheap and i want it to run forever. whether its people not oiling correctly or whatever, im not taking the chance.

well its a good thing no one is holding a gun to your head and making you put on one your car that has a turbo then is it.
 
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gorillaxj

Always building hardly wheeling
Location
SLC
i just read this and checked my intake, housing and everyhtng elss i could around and after the intake on my ranger. lot of dirt b4 filter none after. take it off raod, dirt raods, street highway and stop and go. no matter the driving contion its still cleaner then my fram was. and i feel the power diffrence. gas milage went up 4 mpg then from stock. cleaner louder faster. revs smother too. take into consideration this is with cat back exhoust and synthetic oil. i did them all i day apart to see if i could tell any diffrence b/c my friend was wondering if he should do them all too. works 4 me. i would swear by it.

also what about a k&n filter that would make blades on a turbo get sharp that an after market cone filter wouldnt do? my friends integra is alot more dirt in his intake after filter then mine is?

i also agree with what meat said "Problems with a K&N filter can be measured the idiot behind the spray can."
 
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anvil

Registered User
Location
Idaho Falls
A filter and cat back exhaust got you 4 MPG!! Maybe you had an orange stuck in your old exhaust. You just don't see that kind of improvement unless there was a problem with the components you replaced.

JameK asked why did everyone start making oiled cotton air filters when K&N's patents ran out? I think it's because they're a big money maker. Everyone reads the adds and the placebo effect begins. You think you should have more power, you step harder on the gas to see if you do, you go faster than you did before, and from then on you "swear by it."
 

waynehartwig

www.jeeperman.com
Location
Mead, WA
bobdog said:
There are proven benefits with the KandNs. There may also be downsides. The OEMs do not use the best parts available. There are thousands of aftermarket parts that provide performance gains over the stock stuff. There are no cars or trucks that can not be made better with aftermarket parts. Stock airbox/filter setups are one area proven to be perfornance limiters. OEMs often make low noise a priority over airflow.
Agreed.
Another thing too, most people clean their K&N filter too often. A clean filter is not a efficient one and will allow some particles of dirt by. The dirtier they get, to a point of course, the more effecient they are.
 

Matt

Active Member
Location
K-town
Ok people, K&N's by farr work better than paper filters. I think people just dont know how to use them right! If your using them on a vehicle, you dont over oil them after cleaning, and you let them dry first! On a atv you run what is called an outerwear over the top of them, and you will never see dirt on the inside of the filter!
 

gorillaxj

Always building hardly wheeling
Location
SLC
you dont have to belive me. but thats what my gas tank told me. mabey i switched from reg to premium too? i dont know thats just what it came down to.....
 

wr250

insert lame comment
Location
hurricane
Spork said:
Maybe I'm just thinking about it way too hard... But wouldn't it all depend on if your filter was the bottleneck in your intake?

yes. on a toyota the bottleneck is the exhaust (fixed easily with a cat-back aftermarket exhaust) and MAF (mass air flow sensor). the MAF is basically a square tube with a door (connected to a position sensor) in it that moves with airflow. it is ~1/2 the size of the intake pipe. you could go with no air filter and would gain nothing (which could you breath easier through, a 1/4" tube or a 2" tube?).if you want to really gain from intake mods you will need to ditch the MAF. for this you will need a different computer, commonly a megasquirt or sds systems (they use map sensors).

and BTW, if you use a k&n in a yamaha m/c or atv, yamaha will NOT warranty any problems that could be related to the air filter (oil burning, carb problems etc). the reason is (acc'd to yamaha) they flow dirt. yes i am a yamaha certified tech.
 
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