K&N Filters 57-0070 57i Series Induction Kit Fits 87-91 325i 325iX

Air Intake Kit

57i Series Induction Kit

57i Series Induction Kit; Incl. Red Air Filter/Tubing/Adaptors/Hardware;

K&N 57i Series induction kits are specifically designed for each different vehicle and will free your car from the size restriction that comes with the factory air box. These economical kits can take a variety of different forms based on vehicle characteristics and available space under the hood. Each kit is designed to provide power throughout the RPM range. The extra surface area of these open-air air filters provides even more airflow at lower restriction than a K&N O/E replacement filter which is limited to the size of the factory air box. The larger air filter also captures and holds more dirt increasing its service life before a cleaning is required (up to 100,000 miles). The filter is either directly attached to the engine carburetor or throttle body or indirectly through a tube assembly running from the filter to the engine. All adapters are made from high quality materials such as steel, aluminum, silicon or reinforced nylon to ensure long life. 57i Series Intakes are not legal for use in California and other US States adopting California emission standards.

K&N Engineering, of Riverside, California, is the inventor and leading innovator of reusable cotton gauze filter technology for automotive applications. From humble beginnings as a family run business over 35 years ago, K&N Engineering, now a truly global company with offices in the U.K. and the Netherlands, continues to exist as a family owned business with an enthusiast mindset and a direct connection with motor sports that carries over throughout all levels of management and manufacturing. Today, K&N exists as both the sales and brand leader for performance filters, and maintains a stocking catalogue of over 3,500 part numbers, including an extensive line of both factory replacement drop-in filters, FIPK (Fuel Injection Performance Kit) applications, and its line of innovative Performance Gold oil filters. The cornerstone of K&N's philosophy has been, and continues to be, that automotive performance does not have to have a shelf life, or to stand at odds with the quality of life of the purchasing consumer or others. Put simply, the benefits of increased performance associated with K&N filters contributes meaningfully towards money savings, fuel savings, and a dramatic reduction in environmental waste for the life of the vehicle in which the filter is installed. K&N appreciates that a little education goes a long way in helping consumers take an active role in thinking for the first time about air filters, and then taking an active stance in choosing the filter that is right for them and best reflects their values and needs. With this choice made, K&N consumers become K&N advocates for life, giving "lifetime" another layer of significance.