Maz
NAXJA Forum User
- Location
- LaCanada, CA
-
Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.
Article on K&N Filters
- Thread starter Maz
- Start date
Hawaiian Style
NAXJA Forum User
- Location
- JAX
Interesting article... Raises some nice questions but provides no answers.
K&N has been around for a long time and is used widely by the pros in street rods, off-road racing, ect, ect. If there was a problem with their filters don't you thing someone would have published an actually study discounting K&N's claims of better flow, increased filtration, and more ponies?
K&N has been around for a long time and is used widely by the pros in street rods, off-road racing, ect, ect. If there was a problem with their filters don't you thing someone would have published an actually study discounting K&N's claims of better flow, increased filtration, and more ponies?
Maz
NAXJA Forum User
- Location
- LaCanada, CA
I think the point is long-term effect on engine life/health. with street rods and off-road racing, or any other performance motor, the span of engine life is probably expected to be shorter than a daily drive.
So, the long-term effect of air intake is dis-regarded. I could be completely wrong on this, but it is just my take on it.
Maz
So, the long-term effect of air intake is dis-regarded. I could be completely wrong on this, but it is just my take on it.
Maz
mengleff
NAXJA Forum User
- Location
- sacramento
i switched to a KN in my dd this summer. didn't notice any gain in hp. didn't give it a second thought until someone posted here that they found fine dust inside their intake airtube. checked mine, and it was dirty. i had noticed my oil getting dirty much faster, and didn't think to make a connection until then. i just changed my oil every 2k miles. i think that in pro applications, a gain of a hp or 2 could be the diff in winning/losing so it's worth it, like the article says a pro vehicle is usually only driven for short periods of time. i think for a daily driver like most of ours are, the small gain in hp is not worth the trade off in clean air. now i just keep a clean paper filter and change it every oil change, no dust in the intake.
I have read several independent tests of aftermarket filters, all concluded after dyno runs that K&N did not add any HP, but the testers gathered it would be a better choice since it will remain free flowing longer....(at the cost of your engine!) They also concluded that the stock filter flowed as good or better then the K&N!
I realized how poorly a K&N worked about 8 yrs ago. I had run it in my 86 XJ...the inside of the filter box was coverd in oil, and silt. Its those fine particles that will literally wear out your engines life. Large particles are less of a worry since they cannot even be forced in between the tight clearances in the engine to do harm to things like bearings and rings. I sincerely think that the K&N filter is what killed my engine, which died one night, after having never leaked any oil, never had any problems what so ever and had oil changes every 1500 miles, this thing was treated like a fine watch.
For a professional race car, they are fine, the engines get rebuilt after every race in some cases, for the real world there is really nothing to gain, but much to lose.
XJguy
I realized how poorly a K&N worked about 8 yrs ago. I had run it in my 86 XJ...the inside of the filter box was coverd in oil, and silt. Its those fine particles that will literally wear out your engines life. Large particles are less of a worry since they cannot even be forced in between the tight clearances in the engine to do harm to things like bearings and rings. I sincerely think that the K&N filter is what killed my engine, which died one night, after having never leaked any oil, never had any problems what so ever and had oil changes every 1500 miles, this thing was treated like a fine watch.
For a professional race car, they are fine, the engines get rebuilt after every race in some cases, for the real world there is really nothing to gain, but much to lose.
XJguy
- Location
- Westminster, SoCal
OK.... I have the K&N on mine since about 60K or so.. now I'm at 132K and still going strong (knock on wood). The way I have mine setup, it'd be easy to spot any "dirt" or contaminants inside of the filter as I am using an exhaust pipe for my tube... so it's nice and silver inside, and guess what...... I can't tell it being dirty as it's still nice and shiny (ok... it got a small trail now of oil... but that's from the valve cover tube).
I also look at my tbody every couple of months, and that is staying nice and clean as well (I give it an occasional cleaning just for kicks though). In any case, I drive 120 miles + each day and I commute across LA in stop and go traffic and on average my engine is breathing freeway crap for 3 hours a day which is as dirty as it gets
I also look at my tbody every couple of months, and that is staying nice and clean as well (I give it an occasional cleaning just for kicks though). In any case, I drive 120 miles + each day and I commute across LA in stop and go traffic and on average my engine is breathing freeway crap for 3 hours a day which is as dirty as it gets
Dr. Dyno
NAXJA Forum User
- Location
- Al Ain, UAE
I've been running a K&N type filter for the last 120k miles. If they were that bad, my engine would have been in the knacker's yard by now. The fact is that my engine doesn't use any oil even with 168k miles racked up, and hardly any dust gets inside my intake. A little bit of fine dust isn't a problem anyway so I don't know why people make a lot of whowha about it.
I live in a desert country where there's a lot of dust in the atmosphere so if anyone's engine could have been at risk from bad air filtration, it's mine. For me the K&N does a very good job and I'm keeping it. I just clean and reoil it more often because it gets dirty pretty quickly. I also change the oil religiously every 3k miles.
I live in a desert country where there's a lot of dust in the atmosphere so if anyone's engine could have been at risk from bad air filtration, it's mine. For me the K&N does a very good job and I'm keeping it. I just clean and reoil it more often because it gets dirty pretty quickly. I also change the oil religiously every 3k miles.
rav
NAXJA Forum User
- Location
- Albany, NY
I have my 6X9 inch K&N cone filter retrofitted in a ZJ air box, so it not only keeps the filter clean but it also works as a Cold air intake, best of both worlds
Ravi
Ravi
Nice that you guys are running the K&N's and you don't have sand in the oil pan. But I want the best filter possible period, and at this point that is a paper filter. Period.
I Just don;t see the point on running one for such a tiny benefit. May as well Run Fram oil filters.
K&N is making their $$ off guy slike us with the 4.0's thinking we have a restrictive filter. Yeah when you're running a 500hp Twincam Race beast you need the higher CFM's....and you take the bad with the good. They get the flow they need and they also get increased wear (on a level you'd never see on a street rig)
But at about 200hp it's a moot point IMHO.
I Just don;t see the point on running one for such a tiny benefit. May as well Run Fram oil filters.
K&N is making their $$ off guy slike us with the 4.0's thinking we have a restrictive filter. Yeah when you're running a 500hp Twincam Race beast you need the higher CFM's....and you take the bad with the good. They get the flow they need and they also get increased wear (on a level you'd never see on a street rig)
But at about 200hp it's a moot point IMHO.
woodrock03
NAXJA Forum User
- Location
- Divide, Colorado
I thought the K&N's were superior until reading this post (and a few others). Someone mentioned Amsoil two-stage filters in passing in another post, so I thought I'd look at their site and see what they had to say.
http://www.amsoil.com/products/ts.html
There's a chart on the site that compares the Amsoil filter to high and low quality paper, as well as oil-wetted gauze (K&N).
Their results (probably biased, but they do specify an SAE J726C test method), show the Amsoil rating highest in the three categories of Filter Life/Dirt Removal/Air Flow, with only the high quality paper rating as high in Dirt Removal.
So - I'm thinking that for me at least, it's either going to be the stock paper filter, or the Amsoil (part #TS-29 for the 4.0L). They're not cheap at $40.45 plus $3.55 for the filter oil, but I think they make a pretty persuasive argument IMHO.
http://www.amsoil.com/products/ts.html
There's a chart on the site that compares the Amsoil filter to high and low quality paper, as well as oil-wetted gauze (K&N).
Their results (probably biased, but they do specify an SAE J726C test method), show the Amsoil rating highest in the three categories of Filter Life/Dirt Removal/Air Flow, with only the high quality paper rating as high in Dirt Removal.
So - I'm thinking that for me at least, it's either going to be the stock paper filter, or the Amsoil (part #TS-29 for the 4.0L). They're not cheap at $40.45 plus $3.55 for the filter oil, but I think they make a pretty persuasive argument IMHO.
i haven't found an "independant" test that knocks k&n filters that was acutally independant. when you read through the fine print of the "test" it has always been sponsored by another air filter manufacturer (or masked as their parent company).
the amsoil "tests" are a good example. if amsoil says that k&n filters are no good, more people will buy amsoil air filters instead.
i'm running a k&n cone on a rusty's air tube. the tube is painted gloss black so it's easy to check for fine particle dust and i have yet to find anything. i threw out the stupid plastic hose clamps and bought some of the "old fashioned" metal screw types to keep things secure and if i know that i'm going to be in really dusty conditions i put the dust sleeve over the filter and wash it out in the dishwasher when i get home.
works fine for me.
the amsoil "tests" are a good example. if amsoil says that k&n filters are no good, more people will buy amsoil air filters instead.
i'm running a k&n cone on a rusty's air tube. the tube is painted gloss black so it's easy to check for fine particle dust and i have yet to find anything. i threw out the stupid plastic hose clamps and bought some of the "old fashioned" metal screw types to keep things secure and if i know that i'm going to be in really dusty conditions i put the dust sleeve over the filter and wash it out in the dishwasher when i get home.
works fine for me.
- Location
- So.Cal. Low Desert
Tru Flow...
How about the Tru Flow filter....it's made out of foam. They were at the Off-Road show at the Fairplex last month.
I don't have a link or address. Anyone familiar with them?
See Ya!
Curt (aka Xtreme XJ)
How about the Tru Flow filter....it's made out of foam. They were at the Off-Road show at the Fairplex last month.
I don't have a link or address. Anyone familiar with them?
See Ya!
Curt (aka Xtreme XJ)
Çrestfa||en
NAXJA Forum User
- Location
- Snohomish, WA
if you go with the amsoil you can just clean it too.
XJbone
NAXJA Forum User
- Location
- Saratoga, NY
Soooooooo, what if I drill a few holes in the stock airbox? Would this help with airflow?
Çrestfa||en
NAXJA Forum User
- Location
- Snohomish, WA
Why bother with all that work? I just run no filter when I need extra power.
Çrestfa||en
NAXJA Forum User
- Location
- Snohomish, WA
Why does any one need 1 more hp if they have a jeep? you got 4wheel drive thats all the power you'll ever need
rockwerks
NAXJA Forum User
- Location
- Chito Beach Resort, WA
K&N makes a foam filter cover for times when you are in very silty or dust areas, I ran one on mine, never had dust problems in the air tube and oil remained clean, You have to remember that before these where ever sold for street use they where tested in desert racing for over 10 years,
ran mine on My xj for 3 years and 60,000 miles withuot any problem, but they must be maintaned like anything else.
In high School we tested the filtering power of air filters in a filter ol honda prelude, with the factory honda filter, an K&N, a fram filter and a few others.
To test we prepared the filters as recommended and lined the places two layers of cheese cloth over the inlet to the engine and left the car to run in the wood shop during class, one filter each day for five days and then repeated the test with different filters different days teh next week. (pretty cool class project)
The conclusion:
Never use a factory honda filter. both tests you could not see through the cheese cloth
the Fram and K&N stopped about the same amount of fine dust both where still white after the two days of testing, the fram was actually a tad dirtier.
I've been using K&N's ever since
ran mine on My xj for 3 years and 60,000 miles withuot any problem, but they must be maintaned like anything else.
In high School we tested the filtering power of air filters in a filter ol honda prelude, with the factory honda filter, an K&N, a fram filter and a few others.
To test we prepared the filters as recommended and lined the places two layers of cheese cloth over the inlet to the engine and left the car to run in the wood shop during class, one filter each day for five days and then repeated the test with different filters different days teh next week. (pretty cool class project)
The conclusion:
Never use a factory honda filter. both tests you could not see through the cheese cloth
the Fram and K&N stopped about the same amount of fine dust both where still white after the two days of testing, the fram was actually a tad dirtier.
I've been using K&N's ever since
