Talk:Vehicle Traction
vehicle_parts and items are completely distinct.
for instance, you can install the metal_sheet item as a roof, halfpanel, aisle, metal_boat_hull and possibly some others I'm missing.
all vehicle_parts have a base item which determines their weight but vehicle_part does not need to share an id with its base item
and no, the underlying item doesn't change, but it gets associated with the vehicle_part