Riding Balls of Fire Group B: Thirty years after the end of Group B rallying, film-maker Helmut Deimel has launched his latest film on rallying’s wildest era. For “Riding Balls of Fire”, the Austrian legend behind the hugely popular “Evolution of Rallying” has gathered together the finest archive footage of the 500 bhp Group B supercars in their prime. Watching this film really shows the extreme pace of evolution of the cars and the sport in the three short years from 1983 to 1986.