K & N Performance Filter for BMW

The Original High-Flow Air Filter Since 1969 K&N Engineering has been designing, manufacturing, and enhancing High-Flow Air Filters for the automotive and motorcycle enthusiast interested in maximizing horsepower and acceleration. Since our humble beginnings we have designed and manufactured over 2,400 High-Flow Air Filters to fit most modern passenger vehicles and over 500 High-Flow Air Intake Systems to fit vehicles driven by enthusiast minded drivers.


The K&N FilterCharger^® air filter is designed to achieve high, virtually unrestricted air flow while maintaining filtration levels critical to ensure long engine life.

Engine Protection, Filtration
Anyone can flow more air. The trick is to flow more air safely. In our opinion we hit the sweet spot – an optimal blend of high air flow, filtration efficiency, durability and dust capacity. We take filtration seriously. K&N Air Filter media has been tested both in-house and by independent labs using the ISO5011 test developed by the Society of Automotive Engineers. In addition we test many of our filters both in and out of the OE airbox ensuring proper fit and function. Our goal is to design filters with the maximum possible airflow achievable while providing guaranteed engine protection.

The Importance of Oil
A K&N Air Filter is made of 4 to 6 layers of cotton gauze sandwiched between two epoxy-coated aluminum wire screens. The cotton is treated with a specially formulated grade of oil causing tackiness throughout the cotton’s microscopic strands. The nature of the cotton allows high volumes of airflow, and when combined with the tackiness of the oil creates a powerful filtering media that ensures engine protection. In contrast, most other media can not maintain the same balance of airflow and filtration throughout the filter's life without sacrificing one or the other. With a K&N Air Filter, there is no sacrifice.


Never Replace Your Air Filter Again
Handmade in the USA and in the United Kingdom using only the finest materials, K&N OE Replacement Air Filters are washable and reusable. Regardless of what you’ve heard, it’s almost impossible to wash your K&N Air Filter too much. Inside our testing laboratory, we have washed and re-oiled one K&N Air Filter more than 100 times and it still performs up to specification. Depending on your driving conditions, we recommend cleaning your air filter every 50,000 miles. To clean and re-oil, purchase our filterRecharger^® service kit and follow the easy instructions.

Fuel Economy
Fuel economy testing and mileage claims are a tricky business. Just ask the EPA, whose website states, “EPA’s fuel economy estimates are designed to allow consumers to comparison shop. Your fuel economy will almost certainly vary from EPA’s fuel economy rating. This is based on a number of factors, such as weather, road conditions, your driving and maintenance habits, and your use of air conditioning.” A lot of exaggerated claims are made in the marketplace by products claiming to improve gas mileage. K&N makes no general fuel economy claims, however we encourage you to try our air filter for yourself. Keeping air filter restriction as low as possible can be an important tool, among others, for maintaining high mileage.