[waterlogged]

Why is this inaccurate? I think it would be more accurate to take into account the sidewall flex instead of the "ideal" diameter of the tire with no loads on it.

Think about the tire spinning at highway speeds and warming up. They will expand and take out the majority of the buldge. However I would also have to go along with everyone that 33 is close evnough, unless it is a bias ply claw they run almost 2 inches short.