There will be two classes of Mardave :-
Class 1 = Any Mardave V12 or Shumacher single piece Chassis with G2 Brushed Motor - NO Diff - Batteries 4.8v NIMHs
Class 2 = Any Mardave V12 or Shumacher single piece Chassis with upto 13.5 Brushless motor and Diff is allowed - Batteries 3.7v Lipo.
If you need further clarification please ask.
Eric