This blow off valve is ideal if you want the loud swoosh without your car stalling out or running rich!

By utilizing a unique air diverting system, you can control exactly how much air you dump to the atmosphere for noise, or the inlet for silence. By sending the vented air back to the inlet (rather than muffling it), there is no restriction and the valve still operates at maximum efficiency.

For cars with sensitive air flow meters such as the STi, the valve can be tuned to vent just enough air back to the inlet to prevent backfiring while still giving the loudest possible blow-off noise. This BOV is fully adjustable by the flip of your wrist. 

TECH TIP: This is a 100% bolt on BOV for your STi, no expensive flanges are required for installation. Installation is very easy and will only take 10 minutes and can be done in your driveway. The blow off valve provides a deep whoosh under heavy boost and is fully adjustable with the flip of your wrist.