Its said the primary function of an air filter is to deliver both high airflow and superior dirt protection. K&N designs their air filters to provide minimum restriction allowing high airflow into an engine. In the vast majority of cases increased airflow will increase engine performance measured by horsepower and throttle response (torque). The performance benefits of maximum airflow are clear, compelling and well documented. That is why so many professional racers are willing to run expensive vehicles with no air filter, as opposed to installing a disposable air filter. They are seeking the additional horsepower and throttle response needed to win the race.
K&N design their air filters to provide superior filtration of the contaminants that can harm your engine while maximizing the airflow characteristics of the filter in question. The ability of an air filter to protect your engine is generally measured using a testing procedure developed by the Society of Automotive Engineers identified as the SAE J726 procedure. They subject a sample of their filter designs to this test procedure using Coarse Test Dust, which includes particles ranging in size from less than 5.5 microns to 176 microns. As a point of reference, a human hair is approximately 50 microns in diameter. The result of the above test procedure is a specific air filtration efficiency number. This efficiency number represents the percentage of test dust retained by the filter and thereby kept out of an engine. Their goal is to design our air filters to achieve maximum airflow while targeting overall filtration efficiency at 98%.
Because no two air filters are alike, the specific airflow and overall filtration efficiency will vary depending on the filter in question. However, you can rest assured that each air filter we sell, has been designed to achieve high air flow while providing superior filtration.
Both air flow and dirt protection are critical to engine performance. For this reason a consumer should always evaluate an air filter based on both its filtration efficiency and air flow capabilities.