Originally posted by Install425
Seems to run about the same open or shut. Pops more with it open on decelerating. I think it just that I can hear it more. Sounds and works really good.
Well, by adding the second pipe on the right, you have in effect shortened the muffler. This results in a leaner mixture, which could be causing the popping on decel.
Well... just wait for someone who know's what they're talking about to reply. Maybe should've posted in the 911 Technical Forum.