K& N air filter

Topic: K& N air filter (Read 998 times) previous topic - next topic

K& N air filter

April 04, 2015, 06:15:33 pm

I'm thinking of going from a conventional air filter to a K & N air filter as I'm told these breath better, and last longer.
What seems to be the consensus on this Topic ?
Rob.

Re: K& N air filter

Reply #1 – April 04, 2015, 06:22:11 pm

Rob,

To breath better it has to have bigger openings between the fibers resulting in more dust being let through. Not on our engine. There was a good discussion on this subject recently but I can't find it now.

Pamela & Mike

Re: K& N air filter

Reply #2 – April 04, 2015, 06:24:39 pm

Use-ta run them on 4x4's, to much of a mess keeping them clean, and the paper filters better. JMOO, your opinion may differ, and that's good with me.

Re: K& N air filter

Reply #3 – April 04, 2015, 06:28:09 pm

Avoid.

I can't immediately find the previous threads, but K&N is not recommended by anyone here.

ETA - here ya go

Aero & K&N & UltraPower

Air Filter Minder plus K&N discussion (split from What did you do to your...

K&N air filter

Re: K& N air filter

Reply #4 – April 04, 2015, 06:58:58 pm

Hi Rob,
You will find that most do not recommend the K & N air filters. There is a reason they make more horsepower at wide open throttle. They do not offer as much air restriction, as they do not clean the air near as well. Many people will advise you against using these filters. If you want better "breathing" for your coach, do the muffler/resonator change, as has been done, and discussed, by many members here.
Raymond

Re: K& N air filter

Reply #5 – April 04, 2015, 07:05:03 pm

Better would be to go to the less restrictive Phenix style intake. Not cheap, big improvement I'm told

Re: K& N air filter

Reply #6 – April 04, 2015, 08:32:29 pm

K and engine killer...

Re: K& N air filter

Reply #7 – April 04, 2015, 08:46:23 pm

Glad to see all the negative comments here as Rob visited us today (they live 10kms away and are new owners and members) and I suggested posting this question to you all.
Rob saw the pit and I told him he can use it anytime!!
JohnH

Re: K& N air filter

Reply #8 – April 04, 2015, 11:14:46 pm

Thank you again John for all your intel and your knowledge regarding foretravel coaches . I really enjoyed meeting you .
We should have a long and prosper friendship
Your friend
Rob.

Re: K& N air filter

Reply #9 – April 05, 2015, 10:07:43 am

Letting in more air sometimes requires more fuel so the engine doesn't run to lean. To get the emissions compliant on some engines they run the fuel lean to begin with. More air sometimes means putting in more fuel and less restrictive exhaust to move out the extra your putting in.

Re: K& N air filter

Reply #10 – April 05, 2015, 03:15:49 pm

Bad idea on a front engine vehicle, terrible idea on a diesel pusher. Monitor your filter minder gauge for the maximum restriction recommended for your engine. CATs, Cummins and Detroits all have different allowable restriction limits. Here are the numbers:

Examples shown in Inches of Water (H20)

Non-Turbo Turbo Natural Gas

Detroit Diesel 25" 20" 20"
Cummins 20" 25" 15"
Caterpillar 30" 30" 15"

Replace with OEM style paper filter

Pierce

Re: K& N air filter

Reply #11 – April 06, 2015, 12:48:12 am

Has anyone else looked at the air intake up around the camera on body and thought "that sure looks like small and restrictive air inlet for a large diesel engine?" Sure looks that way to me.

Re: K& N air filter

Reply #12 – April 06, 2015, 01:43:06 am

I have had the same thought... in fact, when I first saw that grill, I couldn't believe that it was the engine air intake. But the same year U320's with ISM's have the same size grill, which blows my mind that much more

Don

Quote from: Chuck Pearson – April 06, 2015, 12:48:12 am

Has anyone else looked at the air intake up around the camera on body and thought "that sure looks like small and restrictive air inlet for a large diesel engine?" Sure looks that way to me.

Re: K& N air filter

Reply #13 – April 06, 2015, 08:00:28 am

Chuck & Don,

Several years ago (before you were members) we had a member that addressed this same thing. Best as I recall and can't find in the old Yahoo files if the member ever did a review on how it preformed. He was looking at an increase in mileage with his "Ram Air" system. Not saying that this is the way I would do it but to answer your basic question is yes there are members that have thought the air intake is a restriction. Here is a link to his pics. something for you to look over. http://www.foreforums.com/index.php?action=media;sa=item;in=557

Pamela & Mike

Re: K& N air filter

Reply #14 – April 06, 2015, 08:35:10 am

The 95 U280 that I had had been modified, I assume by the factory, to add an inlet on the roadside wall above the taillight. It was about 4X6 and allowed all air from the hollow rear cap to enter the air filter.
Gary B

Re: K& N air filter

Reply #15 – April 06, 2015, 10:12:19 am

The air restriction monitor is a "tell tale" and is located on the engine side of the air cleaner element. After using full throttle going on a freeway entrance, you should be able to check the reading at the next stop and check the maximum restriction recorded against the factory numbers for your engine. If the tell tale has moved up at all and the air cleaner element is recent, it might indicate a restrictive intake design. At highway cruising speeds, the engine air requirements are much lower than at full throttle.

Here is an attached link to the tell tale restriction gauge that all of our engines should have: Filter Minder Air Restriction Gauge Direct Mount 20lb, C3550100820, Engineere...

If you really wanted to check the efficiency of your intake system, here is a page of options for either digital manometers or the old fashion kind. Pretty inexpensive: Amazon.com: manometer Just run a tube up into the stateroom and have someone watch it while you drive. The digital type probably will have a setting to record the highest restriction.

Pierce

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Re: K& N air filter

Reply #16 – April 07, 2015, 08:57:34 am

Quote from: Dave Head – April 04, 2015, 07:05:03 pm

Better would be to go to the less restrictive Phenix style intake. Not cheap, big improvement I'm told

What is the "Phenix style intake"? I haven't seen one in person and I can't seem to find any pictures that show it. Thanks!

Re: K& N air filter

Reply #17 – April 07, 2015, 12:02:10 pm

My take on that "Ram Air Intake" that was posted makes me scratch my head at it! One of the reasons I made my little deflector I have put over the air intake/ camera grille is because a few years back while coming over the mtn between Yuma and san Diego during winter we hit some real rain and snow that actually was "sucked" into the intake and caused the Filter to get soaking wet. I did not know this and wondered why the engine was having a hard time to keep running like normal. Once stopped at destination I took out filter (I thought it was blocked with road crap etc) and got a surprise to see it soaking wet! I left it out all night under coach to try and dry and reinstalled it in the morning and all was well again.
So, surely something of this design would allow lots of moisture to enter piping and cause problems, or am I wrong?
JohnH

Re: K& N air filter

Reply #18 – April 07, 2015, 01:28:09 pm

John, no doubt it's a consideration though there are ways to deal with it. Aerodynamically speaking I wouldn't be surprised to find that the rear of the coach, including area of air intake, is running at a negative air pressure...partial vacuum. That's probably why the backside of these things tend to attract and hold dirt so well. That's exactly the area where you don't want your air intake from a performance standpoint but like Pierce has pointed out it may or may not be a problem.

Almost all modern vehicles take advantage of ram air intakes for a cheap performance boost. They have the same possibility of sucking in rain but with dams, deflectors etc manage to divert water before it hits filter.

Re: K& N air filter

Reply #19 – April 07, 2015, 02:15:09 pm

Chuck has it right as the cannister the air filter element goes into has a water drain grommet at the bottom so the filter is less likely to get soaked.

Snow, on the other hand would soak the filter.

Pierce

Re: K& N air filter

Reply #20 – April 07, 2015, 03:07:56 pm

yes I know there is a drain but do not think it does much good as the air would be "soaked" with the moisture IMHO.
A lot of the Ram airs I think are protected in area not directly in line with rain..
Maybe Im all wrong but just do not like any chance of wet air getting into system if I can help it.
JohnH

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