Installed the mbrp exhaust today. I was told when I ordered it, that it was the sport series. But I ended up with the performance series. I wanted a chambered muffler so I didnt have to deal with packing but oh well. But this thing sounds awesome! I called mbrp and the guy said they only make the performance series for the 850. I do have a leak where the elbow goes into the muffler Im guessing some muffler seal compound or a weld would fix it but I dont own a welder any thoughts?