Agreed - I'd be very concerned about clearance, hopping curbs and whatnot.

Running out the back is also very nice and quite, relatively. Furthermore, if you run out the back... it's a whole lot easier to swivel the exhaust to the other side to deal with a need to get quieter!

Not sure what center tunnel muffler you have in mind, but I have a tough time making sound with only one Dynomax race bullet muffler at even a normal track (home track is Waterford Hills, where I need 3 to get the job done). Also note that if you run the exhaust out back as per stock - you can fit a huge oval muffler very easily in the stock location.