In article >,
AZGuy > wrote:
>
>Actually the study results for % efficiency are very similar to what
>was at one time posted on the K&N website (don't know if it still is).
>K&N did report that paper filters had a typical filtration efficiency
>of 98% and that K&N were about 96%. As presented, and with just that
>one bit of info (not all the other tests in SPICER.htm) they said that
>for the slight increase in dirt being passed, the 2% difference, you
>got the big benefits of increased airflow.

_Twice_ the dirt gets passed.