The T51 was the last Cooper conceived for Formula 2 with a 1500cc engine. The project was also used for Formula 1, where the official cars adopted the 2495cc Climax FPF engines. The 1959-1960 seasons were exceptional, with Jack Brabham winning the title in '59; very competitive was also Stirling Moss with the T51 of the Walker team. Beyond the Climax, some teams tried other engine combinations: Atkins and Scuderia Centro-Sud tried the Maserati road; Alf Francis and Rob Walker thought about using a BRM while in 1960 the Scuderia Castellotti chose a Ferrari engine. The T51 soon became an exceptional vehicle for many private teams who also used it in the Tasman Cup and in the Intercontinental F1 of 1961.