The K&N 57i Series Induction kit for the 02-07 Subaru WRX & STI combines the efficiency of a high flow K&N air filter and mounting adapter with the factory Subaru intake tract. K&N utilizes their largest signature conical air filter able to fit for maximize filtration. The air filter is attached to a rotationally molded, high-density, polyethylene velocity stack to enhance the intake charge by creating an efficient air stream free of power-robbing turbulence. A high quality MAF sensor housing keeps sensor readings in check.
The 57 series intake system will increase performance with as little hardware as possible while retaining the stock intake tract to minimize noise. This kit mounts to the factory intake mounting locations with common hand tools. All necessary hardware is included for a complete and clean installation.