2 1/2" or 3"

Looking for input on exhaust size. 71 Duster 4-sp, 496 stroker with tti headers. What are the pros and cons. Car will be street/strip, no cage so have to stay above 11.50 for now so not looking for maximum output from this motor. Are there clearance issues with the 3" system? Oh, I plan to use the tti x-pipe system. Don't want a tinny sound. Muffler recommendations? Thanks FABO