If what you want is something that makes NOISE when you let up off the throttle then you're looking for something other than the Bosch. The Bosch has been known to make a "hooting" noise, but what most people think of when they think of the sound that a BOV makes, they're thinking of one that vents to atmosphere.
You CAN do this with your car, but keep in mind that when it does this, you can end up with issues with how the car runs. The factory electronics measure air before it enters the turbo, and the BOV lets some of that air out in order to relieve pressure between the turbo and the throttle plate. This is so that you don't get compressor surge ruining the turbo. The problem is that the ECU still thinks that that air is there, and needs fuel to burn. The result (if you're lucky) is that it runs really really rich for a bit every time that you shift. If you're not lucky, the engine will stall.
You can learn to avoid the stalling issue with how you handle the gas, but it's still annoying.
