Les Leston began racing with his SS100 in 1949 after which he turned to F3 in 1950. Below are some of the highlights from his highly successful motor racing career:

• British F3 Champion 1954
• British Saloon Car Champion 1958
• British GT Champion 1961

1950:

• Raced Keift 500cc F3 with no success.

1951:

• Drove in 18 F3 events, winning 6.

1952:

• Built a "Leston Special" F3 Car
• Won 16 events including the Luxembourg GP. 
• Lap records at Brands, Silverstone, Porrentruy, Rouen and Namur.
• British F3 hill climb Champion.
• BRDC Seaman Trophy.

1953:

• Works driver for Cooper.
• Won 18 events.
• Lap records at Brands Hatch, Silverstone, Goodwood and Crystal Palace.
• 2nd in the British F3 Championship.

1954:

• Works driver for Cooper.
• Drove Connaught sports car for Peter Bell Stable.
• Won 17 events in F3 and Formula Libre.
• 13 lap records.
• British F3 Champion.

1955:

• Works driver for F1 Connaught GP Team.
• Ran own Cooper Sports Car.
• Won 17 events - F3 and 1500 Sports.

1956:

• Works driver for F1 Connaught GP Team.
• Ran own Cooper F2 Car.
• Won 12 events - Sports 1500.
• 2nd Brands Hatch F1.
• 3rd Goodwood F1.

1957:

• Works driver for F1 Connaught GP Team.
• Works driver for F1 BRM GP Team.
• Works driver for Aston Martin.
• Ran own F2 Cooper winning 8 events.
• 5th Pau F1.

1958:

• Raced and Rallied own Riley 1.5
• Won 16 events.
• British Saloon Car Champion.

1959:

• Raced and Rallied own Riley 1.5
• Won 11 events.

1960:

• Works driver for Volvo.
• Won 8 events for Volvo.
• Works driver for Rootes, competing in Rallies.

1961:

• Raced own Lotus Elite.
• Won 14 races with his Lotus.
• Works driver for Ford America.
• British GT Champion.

1962:

• Raced own Lotus Elite winning 8 events.

1963:

• Raced own Lotus Elite winning 3 events.

In addition to the above Les Leston took part in the following:

• Le Mans 24hrs 5 times
• Monte Carlo Rally 5 times
• RAC Rally 4 times
• Tour de France 2 times
• Alpine Rally 4 times
• Leige/Sofia/Leige 3 times
• Nurburgring 1000km 3 times

Furthermore he has also driven for the works Standard Triumph Team and Austin Healey Team.