k&n air filters

howdy all,has any had good luck with k&n airfilter and does these filter make a diffident in performance thanks marc

I see no one has answered so I'll renew the thread. A friend of mine just pointed these out to me--apparently there's an STC to use them. Does anyone have any experience with these?

Thx.

You will possibly gain a little manifold pressure, but you will pay for the gain with a filter that doesn't filter worth a damn. Don't believe me? Hold one up to a light source and see all of the holes. If you're going to fly in a dirty environment (dirt strips) your engine will appreciate a better filter.

Works good last long time. Same as the car types. I cant see any improved flow over a Brackett air filter, but it has to be better then the paper filters. No replacement times!

Been using one for 5 yr / 500 hr. I fly off grass and water. Not very dirty. Will let you know in another 15 yr how it did.

K & N filter

If you are looking for an increase in performance, just take your filter off and fly around the pattern one time and compare it to flying with your normal filter in place. I can 99.9% guarantee you will not see an increase in performance. I 've tried it on different planes. Can't beat the paper filter for filtering ability. like Dough Head said, just hold it it up to a light and look at it, how much can it be filtering?

k&N

maybe an advantage on float planes and flying in the rain over paper getting wet :roll: :roll: Pat

Currently have over 1000 hours on a K & N. Flying the sandy beaches never had a problem I have pulled it off and cleaned it randomly and found sand & other fine materials in the filter. The oiled fabric catches alot of debris. Did a static run up with digital tach checker and DID notice a little difference in rpm between no filter, the K & N & the standard paper filter. Haven't tried the foam Brackett Filters though.

The dirt track stock car guy's be running K & N filters for years, most of the time on engines that cost 30 grand or more, I don't care where you fly out of it don't get any dirtier then dirt track, unless it's racing in the desert.

Glenn

These filters do flow more air and filter out finer particles do to the advanced technology I use one on my stroker cub it's a. Notable difference on engines that take a big breath

would one of you guys know the K@N filter # for a PA-18 round filter?
thanks,Aurele

K & N part number CPE1151 for the certified 1, you could find the cross reference # for the non certified part at National Aircraft Parts of America or any K & N dealer.

I just saw one - looked like my stock J3 filter. I swore off Brackett after it cracked my hand made cowl, and would just as soon replace the Super D filter with something I do not have to replace each and every year. I am going to look in to it.

thank you for the #

Ok fellas, I finally found the graphs that I was looking for on my computer. These are from an independent ISO lab that does testing for many of the auto manufacturers. Maybe they will help you see in a visual way how different filters perform. Granted, these tests were performed on automobile filters, but it's the same media for your airplane. You K&N fans might want to take a close look.





"The chart below is, in my opinion, the most meaningful and represents the elements performance ability over the life of the element. The aftermarket company will never show you a chart like this, even though the ISO tests performed by each manufacturer, reveals all of this data. It’s what they don’t show you that you need to worry about. Well, here it is!





Dirt is dosed into each element at the rate of 9.8 grams per minute, at a steady 350 cfm (350 cfm represents a moderate load, analogous to towing an 8000 lb trailer at a steady highway speed). The test ends when restriction reaches 10 iwc over its start test value. After 350 grams, all but one of the elements has ballistically exceeded the stock elements resistance level. For 3 of these “competitors” the test had to ended only 1/3rd into the total Delco dust dosage, because each became too restricted to continue. Worse, those elements are letting lots more of that dirt into the motor, as shown earlier, AND…you are paying for all these…”benefits”.



Just for reference, that colorful plastic gauge thingy on the air box begins to retract from green to red at 15 iwc. You can see how much dirt it takes to get to that level of restriction. At this level, the Delco element accommodates twice the dirt quantity of the worst half of the contenders.



Subjectively, I am somewhat impressed by the numbers that the Wix element produced, showing minimal resistance for over a half pound of dirt. These tests were conducted at 350 cfm, and are unfortunately lacking in completeness due to this point alone, my only criticism. Fortunately however, high flow resistance levels can be closely predicted, as was done for the 700 cfm restriction bars discussed earlier. Basically, each of the elements follows a similar correlation. If you increase flow rate, the resistance level will increase with the square of flow rate. In other words doubling flow rate yields a resistance level about 4 (2 times 2) times. At 250 grams of dirt, the 7.0 iwc (Wix) and 10.5 iwc (stock) levels become 28 and 42 iwc, a significant difference. Since the Wix appears to perform very well this way, while still providing decent filtering efficiency, it might be considered a practical alternative, particularly in performance applications where airflow is raised further beyond stock levels, say over 1000 cfm. The exponential growth rate of resistance must be considered for these cases."



I'm not here to butt heads with anyone, I just hope that you will look at these graphs with an open mind and realize what a big difference there is in air filters for your $20,000 to $50,000 dollar engine.

Thx for posting the info.

I really don't know what a K&N filter is made of, but my Bracket filter is a foam impregnated with some kind of oil. I wonder how it relates to the K&N in terms of dirt protection?

Another point probably worth considering is that these aircraft engines are operated on the ground for such a small portion of their lives. It may not be relevant to compare tests for ground-based engines. Dunno. Clearly the K&N doesn't filter as well, but we don't tend to fly in dusty air.

Interesting.

Those graphs are rather amazing. Back in my Baja days, most all the racers, bike and car, used K&N filters. Some buggys would put a foam filter over the K&N and when the engine started to sputter they would remove the foam and just run the K&N. I never had a problem with dirt getting through, even riding through all that talc dust in the dry lakebeds.

From my memory, the K&N was a gauze material inside a pleated wire mesh, and the gauze was oiled.

I don't believe anyone used any of the stock filters back then. Pits were few and far between I have no idea what everyone is using now. With the high-tec pits they can change just about everything out now every 50 miles. Sure would like to hear from a K&N rep as to why they perform so poorly in the above tests. Maybe everything has just gotten that much better while K&N stayed the same.

Gary

could you wash out a bracket filter and spray it with k&n oil.