Perrin Drop-In Panel Filter WRX / STI (2002-2007) Nissan Comes in 57mm and 61mm

Comes in 57mm and 61mm width

smoothly transitioning from a 2

The specific timing of when the reflected sound waves re-join the main exhaust flow creates a one-hundred-and-eighty-degree out-of-phase sound wave that cancels out problematic frequencies

Invidia has finally released a standard size

Radium FPRs are tested using a common high flowing Walbro 255lph pump

Perrin Drop-In Panel Filter WRX / STI (2002-2007) Nissan Comes in 57mm and 61mmThe Perrin drop in air filter for the Subaru WRX & STI uses a 2 stage foam filtration element to improve airflow in your stock air box; providing improved power and airflow while removing harmful particles from the incoming air. Using a special oil coating, the foam filter catches dirt particles while allowing air to pass unimpeded through the high flow foam. This WRX STI 2002 2007 filter can be cleaned and re oiled using the Perrin cleaning kit, sold