I installed my my mbrp 4" exhaust today along with my 5" angle cut tip and Afe drop in filter. A two hour job for everything and then went for a test run. Idle is almost exactly same noise as exhaust just a bit deeper tone. When putting the pedal to the metal it has a roar inside the cab that sounds like the tailpipe wants in the rear passenger door. Don't really care for that part as it is too loud and takes away from the turbo noise. Did not notice any more whistle whatsoever. Everything went on and bolted up fine except for the 5" tip. It vibrates at idle and was a martha focker to tighten. The afe was a martha too, twice as hard as a factory and they are hard to get the top of the box back on. Thinking about welding the tip on unless anyone else has some helpful tips.

 

I have a MBRP SS dual exhaust but welded on. The tips are bolted but I never have a problem with them. Maybe since the entire system is welded, there is less vibration being generated . I didn't want the tips welded because I wanted to be able to remove them if they ever got bent or started to rust. I doubt they will but better safe than sorry.

 

Another two days of driving the truck and some more observations. Engine is smoother when shifting and turbo does not have the lag or mid-range hit that it had before. Cruising at 73 mph egt's are down 75 deg. Boost psi went from 22.75 to 23.75 at wot. Fuel mileage seems to be down so far, even on the trip computer too. Also cruising boost at 73 mph is up too so maybe this is where my fuel is going. Hope it is just a fluke, if my mileage goes to pot, so will the system. It is still loud on the highway and will be annoying pulling anything at all.

 

If it's to loud, your to old.