Wanted to throw my 2 cents in on the MBRP 4" T-back exhaust. I installed it on an 07 CC with my dad. First off the install took us several hours, due to saw issues. Broke dads, then had to go buy another. I guess since mine is still pretty new, the old hangers had not grown into the rubber hangers and they popped right out. Cut the pipe in a few places 1-to get the down pipe out 2- i had welded a section of straight pipe in where the muffler was, and had to cut it to get it out over the axle. The turbo clamp is not real easy to get to on a lifted truck, but it too was easy. Everything fit up well, with the exception of the new clamps. Seems that they were not really clamping down the pipes, and it would allow them to rotate and leak. So we took a grinder to the edges and took a little metal off. After that they fit perfect. I did install the cat and muff deletes too. Once everything was done I was itching to crank it. All I can say is WOW. The sound is awesome. Like a jet until you stomp it and get it to WOT. Then it sounds like a freeking race motor. I did not notice any power loss in the low end or top, and it does seem peppier throughout. Made the drive back home (@ 50 miles) with windows down and no radio, and the sounds is just insane. All the guy on here were right about the sound of the straight pipe 4". I did not notice any drone either, but that may change with the windows up. I do not see any fuel gains, seeing as you tend to keep your foot in it. I gave it 2 thumbs up, less the extra grinding to make sure of a good tight fit.

 

Careful with the T-back references. That means something completely different in states with beachfontage!!

Amen to the sound. It is killer.

Here is a link a before vs after video on mine. make sure you turn up the sound!

stock vs turbo back

 

haha... tback, i get it ... you were probably already salivating before you realized it was just another exhaust thread !! !