[Nonfractal]

In rc12 , as in slot cars, 
A gripper surface requires a stiffer chassis design.
Carpet was indeed the death knell of the UK phantom and the Schumacher lexan cars.
No amount of rework and retrofit could make them competitive.

The US based companies (like associated electrics)  had developed cars for tamac adapted well to carpet.
It took Cecil schumacher and his team a while to develop a carpet capable car. The schumacher  "C"
I don"t think Neal Francis and his Phantom team ever produced a carpet car 

AlanW