Stock Novice Class? Two different items going on....Class and Run Group.
RUN GROUPS are assigned by experience and ability. If it is your first driving school, regargless how many mods the car has, you will start out in the "Novice" Green run group.
The CLASS (where the mods are factored in) comes into play when handing out the awards.
Stock II Class = (Bone stock Gen II Viper + pads & ducts)