Originally Posted by tamster00
The flap in the muffler still opens and closes when the car is idle and in motion.
I've noticed that mine stays closed (quiet) during startup of the car and warm-up. After a few minutes of idling and letting the car warm, I can hear it open, and afterwards it remains open when I'm driving--even in all low RPMs. I didn't do it before, and now both exhaust tips dirty in the same amount, whereas before the upgrade, the left one would always remain closed in the low RPMs, resulting in the right side working by itself and the overall sound being quieter. Well, in any way, whatever they change with the valve makes the exhuast louder and throatier, and I love it!