Yes your right there is a special tool for adjusting the BBV, it comes when you buy a new a valve; however what I'm talking about is the actual foot on the SC. When the valve is closed the little metal end of the rod is resting on a screw type adjuster on the SC base itself. The only way to adjust this piece is with the SC off the car. You flip the SC upside down to see the valve, and close it by hand. When it hits the adjuster the valve should be completely closed. Mine was not, thus leaking boost. The adjuster can be adjusted up or down using a Allen tool underneath the SC.