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OT: High performance air filter: K & N. is their air filter oil anything special?

The best place for a K&N is on the water, good for keeping the bugs and salamanders out of the intake....no need to oil ....:D
On land......If oiled to much, not good, if not enough oil ,worse yet.
There is a short window where the filter is just right, but then it still is allowing more grit to pass than a quality paper element.
Great if your racing for 10 seconds on the strip, or pulling tractors, list goes on and on.......but not for extended periods of time.
Road dirt is just as bad, may not be the clouds of dust as moto, but its there.
But...it looks so cooooooool.:smoking:
And once installed it has to be a least 25% more HP, you can just feel all that new free power....yea right:rolleyes5:
Let me add I'm not bashing them, I ran them on multiple toys I had, did what they needed to do.
But you won't find one in my Lexus LS ..............
 
A K&N will filter in applications where any other filter will plug up.
But it has to be the right application. It needs to be on the intake
of an engine. That is important. Engines have reversion pulses
from the cam overlap period. That means, a small positive pressure
pulse comes back through the carburetor (or throttle body), amidst
all the majority of the vacuum that is predominantly present. This
reversion pulse serves to knock dirt off the K&N filter fabric. It keeps
filters clean, especially in sandy desert usage environments, where
a normal paper filter would cake completely up. It is the intake pulses
of the engine that keep the hospital gauze in dynamic motion and
that motion prevents the dirt particles from caking up. I might think
air compressors without a reversion pulse, and just straight up suction
pulses would effectively keep the gauze element moving effectively too.
But a pulsating intake suction is the key to their efficacy. A constant
suction is not the right use to make a K&N filter work to it's design
potential. They are good filters. You just need to know a bit about
the engineering behind them.

-Doozer
 
I rode with a guy who had four K&N singles on a Honda 750. He upped the main jet in the bottom bowl.
I tried looking at my spark plugs after a open throttle run on some open roads.

If the air flow is greater, and what I read is crappier, then the mixture is adjusted by a vehicle computer.
Otherwise the mixture has to be trimmed manually. If paper filters are better brand new but clog faster, is that better.
Surely not environmental friendly or wallet friendly.
 
I followed the link to O Reilly...not sure the reason......
So $350 bucks for a K&N kit....ok
An ac delco OEM stock filter is $21 at Rockauto...I picked the most expensive one.......
So $350 /$21=16.6
So, I can change the filter every year for 16 years and don't have to oil, clean or worry that the oil has drained away and I'm just pulling in dirt.
Add oil, soap, time I could probably change filters for another 3 years easy
Where are the money savings????
Unless you keep said vehicle for over 19 years the K&N is the money pit.

This is all in relation to a vehicle driven on the roads, not racing or performance venues.
 
As a couple have mentioned I tried a K&N years ago on my F150 and noted the fine dirt inside the carburetor (I said "years ago"!). That observation made me just use regular air filters. I don't bracket race so if it gives a tiny bit of more horsepower that don't matter to me.
 
I followed the link to O Reilly...not sure the reason......
So $350 bucks for a K&N kit....ok
An ac delco OEM stock filter is $21 at Rockauto...I picked the most expensive one.......
So $350 /$21=16.6
So, I can change the filter every year for 16 years and don't have to oil, clean or worry that the oil has drained away and I'm just pulling in dirt.
Add oil, soap, time I could probably change filters for another 3 years easy
Where are the money savings????
Unless you keep said vehicle for over 19 years the K&N is the money pit.

This is all in relation to a vehicle driven on the roads, not racing or performance venues.
No, that is a pre-filter that sits in front of your paper filter. Might be able to double or triple the life on a paper filter.
I would not buy that.

My ordinary K&N air filter is around $75. That's about 2.5-3 times the cost of paper.
And the layer of cotton is thicker than paper.
 
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Having used K&N filters -- and seen the dust accumulating on the inside of the intake boot post filter -- my advice would be to anoint K&N filters with gasoline so they burn better in the trash fire.
You might have over oil the filter and it bled it's guts all over you intake manifold.
Might be normal dust you would have never seen if you didn't have a sticky icky intake tube.

Internet comments do not like K&N.
 
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It's got the special magic price increasing additive otherwise known as marketing.
 
A K&N will filter in applications where any other filter will plug up.
But it has to be the right application. It needs to be on the intake
of an engine. That is important. Engines have reversion pulses
from the cam overlap period. That means, a small positive pressure
pulse comes back through the carburetor (or throttle body), amidst
all the majority of the vacuum that is predominantly present. This
reversion pulse serves to knock dirt off the K&N filter fabric. It keeps
filters clean, especially in sandy desert usage environments, where
a normal paper filter would cake completely up. It is the intake pulses
of the engine that keep the hospital gauze in dynamic motion and
that motion prevents the dirt particles from caking up. I might think
air compressors without a reversion pulse, and just straight up suction
pulses would effectively keep the gauze element moving effectively too.
But a pulsating intake suction is the key to their efficacy. A constant
suction is not the right use to make a K&N filter work to it's design
potential. They are good filters. You just need to know a bit about
the engineering behind them.

-Doozer
Gee, this is the first time that I have heard that "Exhaust Reversion" as being a good thing for an Engine! I am surprised that K&N doesn't mention that benefit.
 
Bar and chain oil as well as way lube has "tackifier" additives. Sticky! but does plug the K&N a bit. oil while warm, and let sit. Or dilute with gas and let that evaporate off .

With that.

I always thought that K&N filters were best used as a suitable support and mounting for a FILTRON oiled FOAM air filter that actually works to keep out the dust and small creatures.
 
Gee, this is the first time that I have heard that "Exhaust Reversion" as being a good thing for an Engine!
I don't know if "good thing" is the best description, but it's been used to increase horsepower at certain rpm's for decades. That's the whole point of collectors and different length open exhausts and expansion chambers and megaphones and reverse cones and all the rest.

I thought K&N's came along for dirty bikes, where paper filters wouldn't hold up to the vibration, pounding, water crossings, and all that. Then once they got popular, well, why not sell to everyone ? They work okay on XR's.
 
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You might have over oil the filter and it bled it's guts all over you intake manifold.
Might be normal dust you would have never seen if you didn't have a sticky icky intake tube.

Internet comments do not like K&N.
If K&N is that fussy about being over oiled, I want nothing to do with them. Strange -- or not -- that not one single OEM uses the concept of oiled cotton gauze filters. Oiled foam yes, but not cotton gauze. Incidentally, the application I used the K&N filters on was a premix 2 stroke so due to reversion there would have been an oil film on the intake tract down stream of the filters whether the K&Ns were over oiled or not.
 
If K&N is that fussy about being over oiled, I want nothing to do with them. Strange -- or not -- that not one single OEM uses the concept of oiled cotton gauze filters. Oiled foam yes, but not cotton gauze. Incidentally, the application I used the K&N filters on was a premix 2 stroke so due to reversion there would have been an oil film on the intake tract down stream of the filters whether the K&Ns were over oiled or not.
They say on the instructions to use their oil. It used to come in a plastic bottle with a folding tip.
The spray can puts out a mist which probably doesn't give the user to over do a lube job.
I've tried ATF and the K & N oil. ATF makes a mess in the air box.
 
Cleaning the K&N filter was a huge messy PIA when I tried one. I didn't have a lot of confidence that it was clean.
 
They say on the instructions to use their oil. It used to come in a plastic bottle with a folding tip.
The spray can puts out a mist which probably doesn't give the user to over do a lube job.
I've tried ATF and the K & N oil. ATF makes a mess in the air box.
I used only the magic K&N stuff . . . both oil and cleaner.
 








 
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