like Brad said its head up w the SAME SIZE tire! 26x8.5 will get to stage with the back tire against a 26x10" tire..its all out of a hat,on who races who..the rest is heads up and try and get the power down,,fastest will not win this race,i think whoever gets down clean has a chance BIG tire is bring what u have heads up 29x10.5 tire is the only limit to that class.