Cargraphic’s Super Sound Version Turbo Back Exhaust Systems for Porsche 991 Turbo |Turbo S with integrated exhaust flaps. This system can be used with either OE flap control (if available) or with the Cargraphic optional performance flap control system. When the flaps are fully opened, 35% of the exhaust fumes flow freely out of the outer tailpipes. The sound is breath taking!