This might be a stupid question, but I only recently started to follow the modifieds closely. In simple terms what is the major differences between UMP, USRA, WISOTA & IMCA modified rules. I know UMP & IMCA do not allow spoilers and I believe IMCA run crate engines but that is all I know. You would think all the organizations would have a set of standardized rules like the Dirt Late Models? I guess that is wishful thinking?
