After the previous year's intense interest from manufacturers for the new Championship, this year the variety of works teams was reduced: Mercedes had decided to stay focused on F1, Alfa Romeo had closed its racing division, Lancia scratched their team (supposedly daunted by the speed of the Jaguars) and Austin-Healey boycotted the event because of the ongoing presence of the sports-car prototypes. But there were still 85 cars registered for this event, of which a full field of 58 arrived for practice as the remaining manufacturers increased their presence.