ottenpat 0 Report post Posted October 6, 2007 This may be a stupid question but I noticed that within my twin exhaust on my e346 320i one outlet has an actuated exhaust flap just within the exhaust outlet tip What is the purpose of this? Seams a little pointless. I do note that when I start the car it is in the closed position. Obviously I do not know what happens during driving. Can anyone enlighten me of this flaps purpose? Quote Share this post Link to post Share on other sites
Yuen 16 Report post Posted October 6, 2007 Hi Patrick, the E36 328i has the same thing, so I think the one on your car works the same way. There is a vacuum hose attached to the exhaust flap, when the car goes past a certain RPM, the flap will open. From what I've read, it's there to increase low-end torque (more backpressure at lower RPMs) and also keeps the exhaust quieter at lower RPMs. Quote Share this post Link to post Share on other sites
