Technically you are allowed 102" of width. Above that you need a wide load permit or a tilt trailer (or both). However your tilt trailer should not exceed 13'6" in the "up" position lest you have unwanted contact with bridges and low overpasses. As far as length is concerned it varies by State, but 102" in width should limit you to about 46 feet in cat length......or less with the new wider tunnels.
T2x