Foam vs paper air filters..., Which is the best? Please say why? |
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Foam vs paper air filters..., Which is the best? Please say why? |
second wind |
Oct 27 2023, 02:58 PM
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#1
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Senior Member Group: Members Posts: 855 Joined: 30-December 10 From: Los Angeles, California Member No.: 12,543 Region Association: Southern California |
Hello Teener World,
I have been a suspended oil foam filter fan since my motocross days (50 years ago) but just bought a brand new Mann paper air filter. My K&N is looking quite worn out and my flaps guy said why bother doing the cleaning and oil anymore? Just buy a quality new paper filter and be on your way. So I did and would love to hear what others have to say about the topic....thank you very much to all!! gg |
second wind |
Oct 27 2023, 03:20 PM
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#2
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Senior Member Group: Members Posts: 855 Joined: 30-December 10 From: Los Angeles, California Member No.: 12,543 Region Association: Southern California |
I think I mean gauze instead of foam....yeah that's it....gauze with oil on it....K&N brand....vs. paper....Thanks,
gg |
brant |
Oct 27 2023, 03:30 PM
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#3
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914 Wizard Group: Members Posts: 11,625 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
The K/N has bigger holes in it to let more air in.
And many tests and people think too many particulates also The stock filter likely filters better |
technicalninja |
Oct 28 2023, 09:16 AM
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#4
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Senior Member Group: Members Posts: 1,233 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region |
I've never seen a factory installed cotton gauze filter on anything...
Ferrari, Lamborghini, Bentley all have paper filters. They are usually very large. The K&N style filter was originally designed for off road racing where the environment could be extremely dusty, and a paper filter would become clogged much earlier. So, unless you're in a dust bowl a paper filter is a FINER filter than a gauze. It does a better job of filtration up to the point it clogs... Another possible issue with the K&N style is a EFI system with a MAF sensor. These are either in the filter housing or the intake tube to the throttle body and the oils that are in the K&N filters tend to coat the fine wire sensor and screw it up. Check engine lights, strange running are the end result. All you have to do is clean the MAF. It's not hard. But, by the third time you're ripping it out and carefully cleaning an almost invisible wire you end up putting a paper filter back in... |
emerygt350 |
Oct 28 2023, 09:54 AM
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#5
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Advanced Member Group: Members Posts: 2,098 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
I used an ancient KN on my old opel gt in the last century, I put one on my mustang and one my 914. I find it let's the engine breath better across the board but of course the value increases at rpm. Cleaning them is easy, maybe every three or 4 years under normal circumstances. I never buy new filters. Is the filtration better or worse? No clue, don't really care. Never had an engine fail because of my air filter. I have had crappy paper filters that choked off an engine though. Paper filters vari in quality greatly and to get the flow of a kn you need a much bigger filter.
That said, the box design in the opel and the 914 makes me cringe. On the opel I went with the normal stack and didn't have to use the box (wouldn't fit on a Weber anyway). On the 914 you don't have a ton of choices on the d-jet. Air has momentum and a 90 degree turn like that helps nothing. Engine masters did a cool comparison this year if you have motortrend. However they couldn't measure how well they cleaned the air, just the effect in power from various papers and a couple of cotton oil filters. |
930cabman |
Oct 28 2023, 03:43 PM
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#6
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Advanced Member Group: Members Posts: 3,065 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States |
paper
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Geezer914 |
Oct 29 2023, 08:06 AM
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#7
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Geezer914 Group: Members Posts: 1,418 Joined: 18-March 09 From: Salem, NJ Member No.: 10,179 Region Association: North East States |
Wix paper element.
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mb911 |
Oct 29 2023, 08:56 AM
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#8
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914 Guru Group: Members Posts: 6,854 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
Did testing 20 years ago for a company I work for and we ran test engines to do the test. K&n filters were equal in filtration to no filter at all. Major engine wear. Better flow but with a major drawback. Paper is way better at filtering. Much less engine wear
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Craigers17 |
Oct 29 2023, 09:13 AM
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#9
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Senior Member Group: Members Posts: 734 Joined: 5-August 17 From: Rome, GA Member No.: 21,317 Region Association: South East States |
So does anyone make paper filters for IDF style carbs? I think all I've ever seen are the ones that need to be oiled. Anyone provide a link?
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Lockwodo |
Oct 29 2023, 09:13 AM
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#10
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Member Group: Members Posts: 201 Joined: 23-December 21 From: Santa Cruz, Californnia Member No.: 26,193 Region Association: Northern California |
Did testing 20 years ago for a company I work for and we ran test engines to do the test. K&n filters were equal in filtration to no filter at all. Major engine wear. Better flow but with a major drawback. Paper is way better at filtering. Much less engine wear Please share data if you have it. |
rhodyguy |
Oct 29 2023, 10:24 AM
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#11
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,080 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
Paper filters for Webers at CIP1.
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Superhawk996 |
Oct 29 2023, 11:29 AM
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#12
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914 Guru Group: Members Posts: 5,827 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Did testing 20 years ago for a company I work for and we ran test engines to do the test. K&n filters were equal in filtration to no filter at all. Major engine wear. Better flow but with a major drawback. Paper is way better at filtering. Much less engine wear Please share data if you have it. Commonly known data in the industry Here is a academic study: https://doi.org/10.1016/j.protcy.2016.05.063 |
JamesJ |
Oct 29 2023, 11:31 AM
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#13
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Member Group: Members Posts: 222 Joined: 30-April 20 From: Sunnyvale, CA Member No.: 24,202 Region Association: Northern California |
You all have me curious now about my foam ITG filters on my carburetor car.
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Superhawk996 |
Oct 29 2023, 11:36 AM
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#14
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914 Guru Group: Members Posts: 5,827 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
You all have me curious now about my foam ITG filters on my carburetor car. Same or more likely worse. Foam typically worse. It depends a lot on foam density and whether you are using single or dual layer foam filter (coarse outer - fine inner) and whether the foam is oiled at all. Very poor filtration compared to paper. Note: I’ve used K&N for years on dual Weber setup. You just have to accept that filtration is (IMG:style_emoticons/default/stromberg.gif) in exchange for better flow. I tried paper filter on Webers once (without rain hat) and got caught in rain. Filter promptly got water logged and that was the end of that. Would be interesting to know how they do with a good rain hat. As a side note: the filtration efficiency of K&N or foam increases as the filter gets dirtier but of course flow goes down accordingly. Another good link to a more definitive ISO test than the basic academic study. https://www.nicoclub.com/archives/kn-vs-oem-filter.html/amp |
mb911 |
Oct 29 2023, 12:00 PM
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#15
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914 Guru Group: Members Posts: 6,854 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
Did testing 20 years ago for a company I work for and we ran test engines to do the test. K&n filters were equal in filtration to no filter at all. Major engine wear. Better flow but with a major drawback. Paper is way better at filtering. Much less engine wear Please share data if you have it. I do not as it was proprietary testing that I performed. NDAs and such |
Superhawk996 |
Oct 29 2023, 12:59 PM
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#16
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914 Guru Group: Members Posts: 5,827 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
I’m still reeling from the death of Brent Brock. His contributions to this forum should not be underestimated with how well he documented so many details of his restoration.
Wanted to take a moment to remind others of the amazing work he did recreating the European style air filter that worked with a standard paper element. This was all hand built (except the center air box - VW part) The details are in his thread. http://www.914world.com/bbs2/index.php?sho...290&st=1720 There are commercial versions of this available (CSP I think?) but they are crazy pricey $900 or more. But if you have a high dollar engine - it is the way to get OEM type filtration and protection for that engine. |
Shivers |
Oct 29 2023, 02:27 PM
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#17
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Senior Member Group: Members Posts: 2,381 Joined: 19-October 20 From: La Quinta, CA Member No.: 24,781 Region Association: Southern California |
This was my drag bike. Klemm research did the head reshape and the porting and I did the rest. I had to make custom intake manifolds to fit two 38mm Keihin's. after shoving those in there, I had room for a couple K&N's. End of that season I disassembled and found two wiesco's totally ruined. I diesel bathed everything, honed the cylinders to seat the new rings, reassembeled with new pistons, the K&N's and Outerwears End of that season it was time for more rings, But that was it. I loved the performance of the K&N's, but don't forget your outerwears. (IMG:style_emoticons/default/smile.gif) |
Robarabian |
Oct 31 2023, 05:41 PM
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#18
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914 A Roo Group: Members Posts: 592 Joined: 11-February 19 From: Simi Valley, Kalifornia Member No.: 22,865 Region Association: Southern California |
Paper filter option for the triple barrel weber IDA 3C's?
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targa72e |
Oct 31 2023, 10:31 PM
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#19
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Member Group: Members Posts: 262 Joined: 11-September 16 From: colorado Member No.: 20,392 Region Association: None |
I use these with my rain hats on my 911 engines. Round filter that fits great when made into a oval.
john |
mb911 |
Nov 1 2023, 04:58 AM
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#20
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914 Guru Group: Members Posts: 6,854 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
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