Small games with a funny effect: You pull off the hose on the right end tube and clamp the lever for the closing flap. Leaves without any effort with a screwdriver within 30 seconds: Dananch is closed the flap in the right end tube, but is pressed on by the exhaust stream. It is therefore permanently open with running engine. With me the workshop has made this change sometimes for troubleshooting. After that the bass-loaded sound is gone. every speed more after circular saw. Very aggressive !!! I don’t like this sound. But I could imagine that it pleases one or the other this tinned sound. Try it out, at your own risk ! However, did not know that it could hurt the car somehow. Whether the sound is so proper however… ? Greetings !