K&N filters

flyingt1954

flyingt1954

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I have a 2006 Jeep Wrangler 4.0 motor and I want to put a K&N filter on the jeep does anybody know if it hurt any of the sensors ,the filter that I want to put on is 57-1514-1 I guess this allow more air into the motor . It is supposed to be good in all 50 states
 
In the TJ's case, the engine gets no more air via a K&N than it does with the OE air intake system. Really. The TJ's air intake system was designed to be 100% non-restrictive and it easily flows more air than the 4.0 can pull at redline rpms and wide-open throttle. Some air intakes like the Camaro Z 28 and Mustang 5.0 are restrictive and their performance can benefit from a K&N air filter but not the TJ.

What the K&N does flow far more easily into the air intake is fine dust, dirt, silicates, etc.. Fine for a street vehicle but not for a Jeep designed to go offroad where conditions are typically dusty and dirty.

In an ISO lab test of air filters, the k&n came in dead-last in in the ability to do a good job of actually keeping the air clean that the engine ingests. Not good.

Having installed one K&N onto a previous TJ years ago before I knew any better, the last thing I would install would be another K&N.
 
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Jerry Bransford said:
In the TJ's case, the engine gets no more air via a K&N than it does with the OE air intake system. Really. The TJ's air intake system was designed to be 100% non-restrictive and it easily flows more air than the 4.0 can pull at redline rpms and wide-open throttle. Some air intakes like the Camaro Z 28 and Mustang 5.0 are restrictive and their performance can benefit from a K&N air filter but not the TJ.

What the K&N does flow far more easily into the air intake is fine dust, dirt, silicates, etc.. Fine for a street vehicle but not for a Jeep designed to go offroad where conditions are typically dusty and dirty.

In an ISO lab test of air filters, the k&n came in dead-last in in the ability to do a good job of actually keeping the air clean that the engine ingests. Not good.

Having installed one K&N onto a previous TJ years ago before I knew any better, the last thing I would install would be another K&N.
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I am running a K&N type filter on mine because I needed space on the fender to mount a air compressor for my onboard air. I will say that there is no difference in how it runs one way or the other. It is a bummer to hear that the k&N is so bad because it is cheaper to buy cleaner than new air filters all of the time. Unfortunately I will have to keep my for a while. Hopefully my super duper sparkplugs can burn fuel and dust haha.
 
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ac_ said:
I am running a K&N type filter on mine because I needed space on the fender to mount a air compressor for my onboard air. I will say that there is no difference in how it runs one way or the other. It is a bummer to hear that the k&N is so bad because it is cheaper to buy cleaner than new air filters all of the time. Unfortunately I will have to keep my for a while. Hopefully my super duper sparkplugs can burn fuel and dust haha.
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Buy yourself that $13 K&N cleaning kit so you can wash and re-oil your filter on a regular (like every three weeks) basis. The oil is the only thing that traps dirt with a K&N and it needs replenishing frequently. It won’t make a K&N a good particulate filter but it will give a bit better dirt capturing ability.
 
Edward Turner said:
Buy yourself that $13 K&N cleaning kit so you can wash and re-oil your filter on a regular (like every three weeks) basis. The oil is the only thing that traps dirt with a K&N and it needs replenishing frequently. It won’t make a K&N a good particulate filter but it will give a bit better dirt capturing ability.
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That's not quite the case on how K&N's filters work. They actually filter better the dirtier they get.

When I used to run a K&N, I was absolutely anal about keeping it clean & oiled using K&N's "FIltercharger" kit because I too believed then that they filtered better when clean & oiled. Then a friend noticed my K&N when we were offroad & suggested we take a look inside the air tube between the K&N and throttle body, and the inside of the throttle body. Then he suggested I wipe my fingers inside the air tube & throttle body. OMG, the inside of the air intake tube & throttle body was absolutely gritty/grimy/dirty. I was both shocked and pissed at how much dirt was inside them, I knew instantly how I had been lied to by K&N.

I was running the K&N then only because I had installed a York compressor for an on-board air system and the factory air intake box would no longer fit so I didn't have the option of going back to it. So instead, I immediately added K&N's Precharger prefilter on top of the K&N as soon as I got home.

When that didn't fit well enough to keep the dirt from coming in from the side and bypassing the Outerwear, I then added a foam Unifilter over the top of the Precharger. Between the two, the amount of dirt getting past the K&N became less frightful.

This is my K&N looked like with the two prefilters I had added pulled back so they can be seen... the last photo shows the York compressor which was why I couldn't just go back to the factory air filter as I would have preferred.

K&N.jpg
K&N1.JPG
CIMG0487Smaller.jpg
 
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You’re entirely correct and I like the unifilter better too. I was totally unclear on what meant to say, the filters do work better dirty but it begins to negate the free flow characteristics they promote. I’d rather use a stock filter and get my marginal gains elsewhere.
 
Now that the K&N air filter subject has been broached, here's one of the charts produced during the ISO test of the air filters. It clearly shows just how much dirt a K&N passes/fails to trap.

The text under the chart is quoted from the ISO test results.

K&N Air Flow Chart.JPG


Per the ISO test results, their words not mine... "In the chart above it’s important to note the different test durations for each filter. The AC Delco filter test ran for 60 minutes before exceeding the restriction limit while the AMSOIL and K&N tests each ran for 20 and 24 minutes respectively before reaching max restriction. In 60 minutes the AC Filter accumulated 574gms of dirt and passed only 0.4gms. After only 24 minutes the K&N had accumulated 221gms of dirt but passed 7.0gms. Compared to the AC, the K&N “plugged up” nearly 3 times faster, passed 18 times more dirt and captured 37% less dirt."
 
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Well at least it's not the worst.

All of my quads and my jeep have K&N's I haven't had any trouble with it, and I keep it clean. (Actually my K&N on my Jeep is a knock off I got for free for testing) I do plan on moving to an actual K&N or better at some point.

I have been running them on my quads for multiple years in a lot dirtier areas than I drive my Jeep.

This is a good discussion, I appreciate it, but like you I have no other choice

But curious @Jerry Bransford what is your set up now? Do you have any recent pictures?

Actually I would like to get rid of the charcoal canister instead if Arizona would let me.
 
Jerry Bransford said:
Now that the K&N air filter subject has been broached, here's one of the charts produced during the ISO test of the air filters. It clearly shows just how much dirt a K&N passes/fails to trap.

The text under the chart is quoted from the ISO test results
View attachment 47793

Per the ISO test results, their words not mine... "In the chart above it’s important to note the different test durations for each filter. The AC Delco filter test ran for 60 minutes before exceeding the restriction limit while the AMSOIL and K&N tests each ran for 20 and 24 minutes respectively before reaching max restriction. In 60 minutes the AC Filter accumulated 574gms of dirt and passed only 0.4gms. After only 24 minutes the K&N had accumulated 221gms of dirt but passed 7.0gms. Compared to the AC, the K&N “plugged up” nearly 3 times faster, passed 18 times more dirt and captured 37% less dirt."
Click to expand...

Jerry, Do you remember how long ago the referenced test was conducted? As far as you know, is the Delco filter still a good choice or has the production been moved or the product changed (cheapened) in this ever changing world we live in today?
 
jgaz said:
Jerry, Do you remember how long ago the referenced test was conducted? As far as you know, is the Delco filter still a good choice or has the production been moved or the product changed (cheapened) in this ever changing world we live in today?
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AC-Delco has a good enough reputation that I'm not worried they would cheapen it. My last AC-Delco air filter looked as good as the first one I ever used many (!) years ago. AC-Delco is considered a top-tier brand in the same way that Spicer, Mopar, etc. parts are.
 
connor grimes said:
@Jerry Bransford what model kn pre filter do i need to fit the wrangler tj FIPK CAI cone shaped filter
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I don't know, a K&N dealer could tell you. But to caution you on just using their prefilter, my K&N prefilter had such a sloppy fit that dust easily made it in around the loose edges. That's why I had to add the foam Unifilter over the top of the K&N prefilter a couple weeks later after I noticed the intake was still getting way too dirty. See post #6 above.
 
I had one on a 97 zj 5.2 and found what jerry suggested a lot of dust going down the tube to the intake, I’ve found paper filters work well and are less maintenance, .02 cents.
 
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I sent Chris a pic of a K and N intake tube with dirt in it . Their dirt ingestion system scares me...no ...it won’t hurt sensors if you let the oil dry , but it will destroy the engine .

Honestly , the stock unit is brilliantly designed.
 
Jerry Bransford said:
That's not quite the case on how K&N's filters work. They actually filter better the dirtier they get.

When I used to run a K&N, I was absolutely anal about keeping it clean & oiled using K&N's "FIltercharger" kit because I too believed then that they filtered better when clean & oiled. Then a friend noticed my K&N when we were offroad & suggested we take a look inside the air tube between the K&N and throttle body, and the inside of the throttle body. Then he suggested I wipe my fingers inside the air tube & throttle body. OMG, the inside of the air intake tube & throttle body was absolutely gritty/grimy/dirty. I was both shocked and pissed at how much dirt was inside them, I knew instantly how I had been lied to by K&N.

I was running the K&N then only because I had installed a York compressor for an on-board air system and the factory air intake box would no longer fit so I didn't have the option of going back to it. So instead, I immediately added K&N's Precharger prefilter on top of the K&N as soon as I got home.

When that didn't fit well enough to keep the dirt from coming in from the side and bypassing the Outerwear, I then added a foam Unifilter over the top of the Precharger. Between the two, the amount of dirt getting past the K&N became less frightful.

This is my K&N looked like with the two prefilters I had added pulled back so they can be seen... the last photo shows the York compressor which was why I couldn't just go back to the factory air filter as I would have preferred.

View attachment 47789 View attachment 47790 View attachment 47791
Click to expand...
Jerry, any chance you know the part # for this kit and if it was C.A.R.B. approved? The smog guy would not test me because I did not have a CARB approved air filter and tube. I realize they aren’t the best. Just trying to find the packaging that will fit my current set up in order to pass.
 
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