DSM's have a MAF. It meters air to account for how much fuel to give the motor. When you vent outside the system NO MATTER WHAT it looses air that was counted when it came in. It results in a rich condition. Period. Will you get the car to idle OK....maybe. Will it be piss rich between shifts...definately. Will it hurt boost responce after shifting....yes. Is it worth it? It's up to you noise or performance. Change to a VPC if you wanna vent.