active exuast?

i was wondering what the active exuast does lol :) whats so "active" about it? sorry if this is a stupid question, but it's just bothering me.

Basically it opens and closes the exaust to the passenger side of the car. Not much of a performance change, but the sport mode is louder then tour.

Wait, on my SL, I have an ECS button that changes the tour/sport option. Is this the same thing as what you guys are talking about? Because I was thinking the tour/sport option had something to do with the springs to make it harder when driving at fast speeds. :o/

ECS is electronically controlled suspension, it tightens up the suspension in 'tour' mode.

Active exhaust also has a sport and tour mode, but the 2 features are unrelated.

Gotcha. I thought the suspension tightens in sport mode because of higher speeds? Hmm....I'm confused....