I suggest that you have the dealer check to be sure there are no other issues, as your vibration issues are not representative of other folks. Request that they set you idle speed in non sport to 700 rpm and see if that mitigates the majority of the vibration. Good Luck.

 

I assumed that the dealer couldn't change my idle speed, but I will ask them. Thanks.

 

They can but may not as this may be deemed a warranty voidable event.

I still believe there is something else going on with your car. Too bad you don't have the COBB AP3, you could scan for fault codes yourself and help to diagnose what is going on here. I am 100% convinced there is a problem that is only surfacing because the center muffler has been eliminated.

If your handy with a wrench, you could reinstall your stock system and see the difference, personally I would run a fault code scan before I did anything else. With the AP3, You can also log your car idling at normal and look for timing corrections or any other anomaly. You then compare it idling with the sport mode. This type of diagnostic testing can really save time and heartbreak. These types of problems unless a fault code is thrown is just not in the service technicians wheelhouse.

 

Since the same thing happened with the Sharkwerks bypass, which went away when I switched back to stock, I'm sure the same (vibration will be eliminated) will happen here once I go back to stock.