Do K&N air filters really filter?

[Church]

Thought y'all might like to know this, I noticed a lot of talk on this board recently about K&N air filters. I used to think these filters were the best filters on the market but I have changed filters after seeing a lot of dirt getting by the K&N! (Yes it was oiled properly.) Not only have I noticed this on my Jeep but I am switching to an Amsoil filter on my 67 truck as well. A lot of Jeepers have noticed that K&N's are letting a lot of dirt get by the filter too. With that being said I have put my flamesuit on (zip). Here is a test that was performed by an independant laboratory.

Here's a more detailed test procedure and conclusive results covering AMSOIL vs. K&N and paper air filters according to the Industry Standard Society of Automotive Engineers (SAE) test standard SAE J726.

Your car's engine "inhales" air that is mixed with fuel for combustion. But air contains an incredible amount of suspended dirt - typically 400 tons of it in a cubic mile. Much of this is microscopic dirt, extremely abrasive, that can cause serious damage inside the engine. Consequently, an air filter is a

An air cleaner must not only trap as much grit as possible, but it should do so without "smothering" the engine, restricting its vital airflow. Thus the most desirable performance characteristics for an air cleaning device are high dirt-trapping efficiency, and minimal airflow restriction as the dirt accumulates.

The Society of Automotive Engineers Test Code J726 specifies the procedures, conditions, equipment, and report format which air filters can be uniformly compared. A standardized dust contaminant is introduced into a specially designed testing apparatus at a controlled rate. Most of the dust will be trapped in the filter undergoing the test; the remainder is captured in an "absolute filter".

The air pressure upstream and downstream of the test unit is monitored. The test terminates when the pressure differential causes a predetermined amount of fluid displacement on a water manometer. By quantifying and comparing weights, pressures, and elapsed time, the experimenter can determine a filters efficiency, capacity and airflow-based life expectancy.

Our J726 trials were conducted at an independent testing facility in the upper midwest. The tests compared Motorvator, K&N, Accel, Fram, and AMSOIL products. The results? AMSOIL proved vastly superior to the competitors' air cleaners as the only air filter to consistently score high marks in all three vital areas of airflow, efficiency and capacity.

The AMSOIL 2-Stage Air Filter traps airborne dust with 99% efficiency; it holds an incredible 281 grams of contaminant (that's over half a pound); and it outlasts the competition. It performs two to four times longer than the others. That's why AMSOIL can confidently recommend a 25,000 mile/1-year service life. And the 2-Stage is actually re-usable, with proper cleaning and re-oiling.