Triumph started to campaign the Spitfire right from the introduction on the US market in 1963. The competitions department was based in California and managed by their genius Kas Kastner. The cars were very successful in regional and divisional events and numerous championships were won. The competition manuals Kastner wrote are still a valuable source for tuning a Spitfire.

A highly successful team in Spitfire racing was Group 44 of Bob Tullius during the later years.