In its second year, Trans-Am rapidly grew - things became real serious. Big names at the steering wheel, and works entries from Chevrolet, Mercury and Ford filled the Over 2000 class, while the pseudo-touring car Porsche stormed the Under 2000 class, wiping out all opponents apart from Alfa Romeo who had to be content with second place.
Manufacturers champion in the big class became Ford for the second year running, but it had been a close battle; Mercury was beaten in the last race, while Chevrolet's attack came too late. A thrilling season with record crowds, and the first shades of professionalism: Mercury was rumoured to race underweight cars. The Mercury/Ford fight would not continue; Mercury had to withdraw, since it made no sense for Ford to have two rival teams.