I'm confused (seriously) to me the amount of tread is the foot print? Squeeze it in or use a wide rim the tread is all that's goning to hit the ground unless you run a huge rim and roll it (the sidewall) over then the inside of the tread wants to go up leaving less surface. The biggest thing that helped me (thanks Kenny) was finding tires that had a flat tread when mounted, then I didn't have to put them in a lathe to make them flat, what a difference!