Cooper T53

The T53 was lower and slimmer than its predecessor, the Cooper T51. It was equipped with a new tubular steel frame clad in aluminium panels. The car weighed 460 kg. Suspension was by double wishbones, coil springs and telescopic dampers all round — a change from Cooper's usual transverse leaf spring at the rear. The T53 was known as the "lowline" Cooper due to its lower engine mounting and more reclined driving position. Power came from the latest version of the 2.5-litre Climax FPF engine, which developed around 240 bhp or 250 HP, driving the rear wheels through a Cooper five-speed gearbox. The ERSA gearbox was replaced with a new five-speed C5S transaxle designed by Cooper designer Owen Maddock and built by Jack Knight Engineering.

In its first race, Jack Brabham drove the T53 to second place in the International Trophy at Silverstone. At its first World Championship event at Monaco, Brabham qualified second but was disqualified in the race after spinning off and receiving a push start. Bruce McLaren finished second to Stirling Moss at Monaco. Brabham then reeled off five wins in a row to secure the World Championship with two events to spare. McLaren finished as runner-up in the Drivers' Championship, and Cooper won the Constructors' Championship. Brabham also won the non-championship Silver City Trophy that season. The Cooper T53 competed in 10 races, achieving 6 victories and 5 pole positions. It was capable of reaching 265 km/h on the fastest circuits.

Cooper turned to the T55 for 1961, but the T53 became a significant sales success, with no fewer than eight teams running examples. Most teams fitted the 1.5-litre Climax FPF Mk. II to comply with the new Formula One regulations, though Scuderia Centro Sud sourced a Maserati engine instead. Despite some success in non-championship events, the privateer runners were largely outclassed in the 1961 World Championship.

The T53 was also used in the short-lived Intercontinental Formula in 1961, fitted with a 2.7-litre version of the FPF engine. Stirling Moss and Jack Brabham won all five races in that series with the car. Several examples made their way to Australia and New Zealand, where they competed in the Tasman Series.

One T53 was shipped to the Indianapolis Motor Speedway for a two-day test in October 1960, where it reached 144.8 mph. In 1961, a Cooper car was presented in the 500 miles of Indianapolis with Jack Brabham as a driver, finishing ninth.

This article is based solely on the supplied corpus. No external sources were consulted; claims that could not be substantiated against the corpus were omitted under the drop-the-claim rule.