K&N Filters factory response

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May 24, 2001, 8:52:01 PM5/24/01
I've used K&N air filters on most of our vehicles, and I thought they worked
very well...until I read internet posts.

After reading various critical posts on K&N filters, I wrote to K&N. Even
though we have one BMW with 400K miles on the original engine...I worried that
the K&N critics might have valid concerns.

Here's the factory response:

>>>Our filters are tested by an outside, independent laboratory. They have
been proven to stop at least 99% of particles on a SAE dust test. This test
uses particles as low as the 0 - 5 micron range and goes up to 20 microns.
For comparison, a paper filter also stops 99% on the same test and the OEM
minimum standard is 96%. Foam is generally the worst media with a typical
efficiency rating of 75 - 85%. To get higher ratings, the foam must be more
dense and therefore way more restrictive. The "tack" characteristic of a K&N
allows for increase filtration without loss of flow as well.
The testing procedure used is SAE J-726 using ISO Test Dust. This test
is the standard of the air filter industry. The test procedure consists of
flowing air through the filter at a constant rate (airflow rate is
determined by the application) while feeding test dust into the air stream
at a rate of 1 gram per cubic meter of air.
As the filter loads with dust the pressure drop across the filter is
increased to maintain the prescribed airflow rate. The test is continued
until the pressure drop increases 10" H2O above the initial restriction of
the clean element (in this case .78" to 10.78" H2O). At this point the test
is terminated. The dirty filter element is then weighed. This weight is
compared to the clean element weight to determine the total Dust Capacity.
The amount of dust retained by the filter is divided by the total amount of
dust fed during the test to determine the Cumulative Efficiency.

The K&N filter achieved the following results:

Dust Capacity: 305 grams

K&N Cumulative Efficiency: 99.05 %
K&N Initial Pass Efficiency: 97.11 %

OEM Paper Cumulative: 99.29 %
OEM Paper Initial Pass: 96.47 %

Holding the filter to the light is useless, pin holes are normal. That
is what makes a K&N filter. There are actually hundreds of microscopic
fibers that cross these holes and when treated with oil, capture and hold
the very fine particles. On the same hand, they allow the filter to flow
more air than paper or foam. The filter is 4 ply cotton gauze unlike some
competitors synthetic material filters. The synthetics do not have the very
small fibers that natural cotton does. Also, the oil can be pulled off of a
foam filter contaminating electronic sensors. It will absorb into cotton
and stay in the media. In fact, Honda and Toyota only recommend K&N filters
when using aftermarket high flow filters as K&N is the only brand of filter
the oil does NOT come off of. They will not cover a failed sensor if foam
filters were used.
We got started over 30 years ago making filters for motorcycles and off
road racers. The filters did so well that these guys wanted them for their
cars and trucks. We started making filters for these applications and here
we are today. If they did not work, we would not still be here and growing
every year.
We now make filters for Chrysler/Mopar, Ford Motorsports, Edelbrock,
Rotax Engines, and Harley Davidson. We come as original equipment on the
2000 Ford Mustang Cobra-R. We even made filters for the Apache helicopters
used in Desert Storm because of maintenance problems with the original paper
design. If they work in these conditions they will work for you. <<<

I appreciate K&N taking the time to reply, and I feel much more confident about
using K&N.

Anthony S

May 24, 2001, 9:55:14 PM5/24/01

That is a very interesting response from them. It is interesting to note
though that all the companies making foam filters have "independent studies"
that show their filters are superior too. Of course, I don't know of anyone
that uses their filters as OEM equipment.

I have a K&N on my SVO mostly because it comes in the handy dandy remove the
factory airbox conical add 15 hp style ;-). It's nice to know that it ought to
filter well too.

Anthony S
'85 SVO
Librarian of the SVO World Order

Stephen Begg

May 24, 2001, 11:01:33 PM5/24/01
If memory serves, the '00 Cobra R uses a K&N air filter as OEM.

'00 GT

"Anthony S" <svon...@cs.compostheap> wrote in message

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