Home » GEMBALLA GT Cabrio – See and Hear The Amazing Porsche 911 Carrera Upgrade » GT_Exhaust_start and play (valve closed) GT_Exhaust_start and play (valve closed) https://www.car-revs-daily.com/wp-content/uploads/2014/11/GT_Exhaust_start-and-play-valve-closed.mp3 “GT_Exhaust_start and play (valve closed)”. Home » GEMBALLA GT Cabrio – See and Hear The Amazing Porsche 911 Carrera Upgrade » GT_Exhaust_start and play (valve closed)