Has anyone COMPLETELY tested air cleaner elements? I have searched and found a lot of “ flow” tests, but not any that compare , flow, capacity, ability to clean the air, how effective the filter is as it collects dirt and lastly price. To me these things are important! Number one with me is how clean the element cleans the air , #2 is flow, #3 is capacity to hold dirt, and lastly the price. Is there a test anywhere that gives these results? About thirty years ago I bought a popular brand X air filter at a parts store and it just looked cheap, I could “ see” through it! If you can see through it, it isn’t going to filter! I then asked for a “Wix” filter and found that it weighed twice as much and had way more paper in it. I have used Wix filters ever since. But still have never seen any comprehensive test results, to support my observations. Bones
Like you say , finding unbiased data is a bust , but I've heard talk that the oiled cloth filters are horrible at keeping the air clean ? Then again, you wonder how good any of them really are ?
I learned how bad the oil type elements are when I used them on moto-cross motorcycles 35 years ago! . Absolutely worthless. Let so much dirt in it wore my rings out in two races! Replaced it with the stock paper element, raced all season on one set of rings. Bones
I know I’ve seen results posted before for filtering, but who knows who they were published by. But never been it posted with respects to flow.
There is no magic air filter that will supper filter the air and give you more power. The better filtration the more restriction IMO. But K&N made claims at first and maybe they still do of both filtration and flow.
^^ K&N filters have been shown to do a poor job of removing contaminants. They do flow well when brand new, but as they start to load up their flow capacity drops below that of stock type paper filters. Cummins has done testing on this and used to have a pdf on their site you could download, they still might. But I read about the poor performance of K&N long before that. And Bones didn't say, but I think it was K&N filters that he had a bad experience with on his motocross bike.
Project Farm on youtube did. Pretty interesting stuff. He tests a lot of things out there and gives unbiased results. Here's a link
The proper air cleaner base where it meets the carburetor will have more effect on air flow improvements.
Dave Vizard has done some pretty in -depth research on air filters.In his book "How to build Horsepower" he has quite a section on flow, with charts etc.Kand N came out on top in most of his in depth research.That said,if they are not kept cleaned and oiled,they will not do their job effectively.If you have not read any of Daves books,I highly recommend.As Salt Flat says, the air cleaner housing is as important as the filter itself..
I've got that Vizard book out in a box somewhere and it is pretty interesting in air flow in the air cleaner section.
There was a discussion about this in the past and it turned into a pissing match like everything on this site seems to do, old guys don't believe in new technology no matter what evidence is provided, one camp only cares about air cleanliness without any regards to air flow, other camp wants flow, whoever talks the loudest thinks they are the winner. The dirty K&N is always compared to the clean paper when comparing flow, always comical, maybe I'll try and look up the last argument so everyone can read it all over and see the same perpetrators talking the loudest.
I found out the hard way in motocross . I had an older used filter and cleaned like K&N recommended,,,,,,I assumed it was fine after oiling . My mistake,,,,,since it was being used on a new build,,,,,,,how was I to know the filter was not flowing good . I fought jetting on that machine for months,,,,literally,,,,,,,. This was a custom mini 80cc machine so it was sensitive to air flow . Anyway,,,,,,I finally switched to an old paper filter to do some testing while I protected the good filter and kept it clean . Instant success,,,,,had to go all the jetting back where it was,,,,,wha5 a relief. Anyway,,,,I’m sure they are good filters,,,,,,,,just not quite the filter that last beyond a certain number of cleanings . Hope this helps someone . Tommy
Out of curiosity, does anyone know how the traditional oil bath filters rate compared to a paper filter. Steve
I recall in the 70’s HRM doing a dyno pull on an engine, one with a “flat” air cleaner then with one using a drop base air cleaner. The drop base made a few more HP. Anyone recall that article?
Yes, I do. As I recall, they attributed the power increase to a smoothing of the air flow and a reduction in turbulence.
There was a thread on this years ago. You'll need to search it. From memory the filtration is okay, but RPM and volume limited on modified engines. Nothing could be worse than those little decorator item filters and helmets people seem compelled to use on flatheads and tri carbs. May as well stuff a rag in the venturi then attempt to tune the engine. I know this has been discussed many times.
I think, may be wrong it’s been years, they also talked about why cowl induction was better that a good scoop. Low pressure v turbulence, or similar. Funny we can recall that, but not my Chem 101 class
https://www.secondstrike.com/Technical/AirCleanerCalc.asp I remember tri power 348s guys would replace the air cleaner with 3 little crome ones and the cars lost power. At Mokan we made a pass with out air cleaners and read the plugs and they looked good put the air cleaners on and made a pass plugs looked rich the stock air cleaner went back on.
To test filters "properly"...would take a good amount of money and time. You can do quicky testing, but even that would take time and money, and would be...well...halfassed. As for the cotton type filters...as time has marched on, so has the cotton filter. Despite what one noted above...the manufactures have listened (to us complainers) and fixed them. About...20 years back, I was somewhat forced to buy a set of cotton filters for a motorcycle. I installed an aftermarket set of carburetors onto one of my bikes engines. Their design would not allow the use of the factory airbox (with paper filter), so I had to buy a set of the main manufacturer of cotton filters. After opening the box, I was HIGHLY...unimpressed. I called them and asked about the fact that I could see actual light rays coming through the filter. Not just ambient light like I figured, but rays of light. They told me that the oil would take care of that. I strongly disagreed, and said that it would take STP to fix this problem. I never bought another K&N filter. BUT... Fast forward to a 2014 when I bought a new (185hp) bike. Guess what, the "factory" had installed a K&N filter into the air box. I pulled it out and looked closely. Wonder of wonders, NO light rays shining through the filter material ! OK...they seem to have fixed their problem. Later I'd bought a second filter as a backup. Same thing, it had enough layers that even the ambient light was somewhat muted. Good for K&N, they learned, and redesigned their filters. So...yes...IF K&N has redesigned all of their filters like the one on my bike, in my opinion, they are now worth a look. As long as when you hold the filter up to the light, and you look at the filter on the opposite from the sun, and there are no "rays" of light, to me, they are now usable. With oil of course ! And yeah, I bought a car K&N for a non-HAMB car about a year ago. I did look closely, and found no light rays shining through, even as I said above, even the ambient light was somewhat dulled, or muted. It now lives in the airbox of that car. So yeah, not only people, but whole companies can change..! Mike
Wish they would have tested the Z/28 LT-1 air filter assembly... Probably would have made more power than the cheap aftermarket 14x3 filter....
In general...you want a filter that is larger, taller, more gradually curved into the carb, more pleats, etc. At least, that's the trends I've seen in the test results I've read. Also, if the filter looks really neat, it probably works like shit.
I just put on my new repop S&H Cobra air cleaner housings, with Wix 42040 filter elements (they're taller). I guess I'll see how they work. Not much different than the Moroso housings and 42055 elements I had before, but they don't have that ugly modern Moroso logo.
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