The AGP External Vent Modification (EVM) is the easiest way to get the famous blow off valve noise, without the need to purchase an aftermarket blow off valve. Your stock blow off valve releases air back into the turbo housing making it very hard to hear. The EVM is a spacer that installs under you stock blow off valve. It has channels to redirect some of that air so it gets released into the atmosphere making the noise. The kit includes the EVM plate and longer bolts.
