This C.A.R.B. approved intake and integrated airbox looks great and has the combined benefits of a short ram intake and a cold air intake without any of the negatives. This system utilizes several unique features in an effort to maintain optimal flow for performance while minimizing turbulence that can cause engine management problems. From a custom conical cloth air-filter element, we use a CFD-designed velocity stack leading to an unique air flow straightener grid. This straightener grid is specifically designed to smooth the incoming air flow as it passes the Mass Air Flow sensor for precise readings. This eliminates the “dead spots” experienced by other aftermarket intakes due to turbulence. No other aftermarket Subaru intake system utilizes these critical design elements. In order to provide a system that looks as good on the outside as the technical advancements happening on the inside, we utilize a one piece design constructed from a high temperature plastic composite. Not only does this save weight compared to the previous metal design, the plastic composite material offers much better heat rejection properties that help keep intake air temperatures cooler. In contrast, intake systems constructed using metal castings or piping can actually retain underhood heat and in turn heat the incoming air. The SF Air Box adds the benefits of a cold air intake to the outstanding performance of the SF Intake. The factory inlet directs cold air from the front grill to the SF Air, which encloses the SF intake. Hot engine bay air that robs horsepower is prevented from entering the intake system. This unique design also separates rainwater from the intake air, eliminating the water ingestion issues that plague in-fender cold air intakes. This COBB SF Intake does not require additional tuning once installed. It is designed to work perfectly with the stock MAF sensor. The filter even comes Pre-Oiled. Simply install and go! Includes the Post MAF Hose.