Car Vehicle Turbo Sound Whistle Exhaust Pipe Tailpipe Fake BOV Blow-off Valve Simulator $ 13.99 Installation: Loosen the bolt on the Turbo Sound Whistle. Insert the the Turbo Sound Whistle into the tailpipe. Tighten the bolt so as not to fall off while driving. Notes: Please make sure the tailpipe is big and long enough to contain the Turbo Sound Whistle. Professional installation is always recommended, products damaged through self-installation will not be refunded. Please check and re-tighten the bolt regularly.