1961 Cooper Climax. Click image to enlarge
Story and photo by Bill Vance
The Indianapolis 500, “The Greatest Spectacle in Racing,” started in 1911. For 50 years, except for an occasional aberration like the unsuccessful 1930s rear-engined racer designed by Harry Miller, the cars’ basic front engine layout remained the same. That began to change in 1961, and in just four years the conversion to rear engines was all but complete.
Rear-engined racers had competed in top level European Grand Prix racing in the 1930s. Consulting engineer Ferdinand Porsche of Volkswagen fame designed a rear-engined racer for Germany’s Auto Union company. Those fearsomely fast 12 and 16 cylinder Auto Unions in the hands of skilled drivers could beat the front-engined Mercedes-Benzes and Alfa Romeos. Mercedes-Benz and Auto Union dominated Grand Prix racing from 1934 to 1939.
Racing gradually revived following the Second World War. In Europe the Auto Union cars were gone, and when the Formula 1 Grand Prix world driving championship was established there in 1950 the drivers ran front-engined cars.
Meanwhile, in 1946 in the London suburb of Surbiton, an Englishman named John Cooper had begun experimenting with tiny cars with their 500-cc single cylinder motorcycle engines behind the driver. The open wheelers’ good power to weight ratio made them surprisingly fast in the 500-cc and Formula 3 classes.
With no driveshaft, the rear-engined cars were smaller and lighter, and the driver sat much lower, reducing frontal area. Famous drivers like Stirling Moss cut their teeth on Coopers.
Cooper’s rear-engined cars grew and advanced through Formula 2, and then by 1957 to Formula 1, where drivers competed for the world championship. Although Cooper’s Coventry Climax 2.0-litre fours gave away half a litre to its competitors, a Cooper finally won its first Grand Prix in 1958.
The writing was on the wall for front-engined cars, and in 1959 and then in ’60, now with a full 2.5-litre, Coopers scored a total of 13 victories, giving Australian driver Jack Brabham world driving championships both years. The rear-engined revolution had begun in Formula 1 and others like Lotus and BRM quickly switched.
In October, 1960 John Cooper brought Brabham and a championship Cooper to Indianapolis for testing. The conservative Indy racing establishment was skeptical that these small, light, rear-engined cars could keep up with big, rugged, Offenhauser-engined Indy roadsters.
In spite of having only 2.5 litres compared with the Offy’s 4.2, Brabham took the little Cooper around at an easy 144.8 mph (233 km/h). Its light weight, more sophisticated suspension and central weight bias made it quicker through the corners. The front row qualifiers for the 1960 race had run about 146 mph (235 km/h), so the Cooper demonstrated that it could be competitive. Some eyebrows were raised along Gasoline Ally.
Encouraged, and enticed by huge Indy purses, Cooper entered Brabham and a Cooper in the 1961 Indy 500. He enlarged the engine to 2.8 litres, tilted it a little to the left, and added some fuel tanks on the left for even better cornering.
The Cooper ran well, qualified on the fifth row, and finished ninth, not a bad start. Its Achilles heel was the Dunlop tires Cooper was contracted to use. When Brabham ran with Dunlops, his tires wore out faster than the competitors’ Firestones, requiring more pit stops. By running slower they lasted longer but the Cooper finished lower. In spite of this the revolution had begun at Indy.
Rear engines were back for 1962, but not from Cooper. California hot rodder Mickey Thompson saw the potential of the rear engine and constructed a team of rear-engined racers with modified Buick aluminum V8s. Driver Dan Gurney had mechanical problems and covered 93 laps, finishing 20th. The Offenhauser powered roadster still ruled Indy.
The Europeans returned for 1963. Englishman Colin Chapman entered Scottish Formula 1 star Jim Clark and Dan Gurney in rear-engined Lotus-Fords powered by modified Ford Fairlane V8 engines. Mickey Thompson was back with his rear-engined car, now Chevrolet powered.
Clark finished second, only 34 seconds behind Parnelli Jones’s front-engined Indy roadster, but it was a controversial victory. Jones’s car began spewing oil onto the track late in the race, sparking heated controversy. Chapman argued vociferously that Jones should have been black flagged and stopped, but tradition dies hard at Indy and he was allowed to continue. Although Clark could pull to within 4.5 seconds of Jones, he found the going too slippery and backed off.
Chapman was back for 1964 with his rear engined Lotuses now powered by aluminum, twin overhead cam, four-valve-per cylinder racing V8s developed by an invigorated Ford Motor Co. Although Clark set the official track record at 159.38 mph (257 km/h), the Dunlop tires again let the Lotuses down. Clark and Gurney both retired early, but Roger Ward reinforced the new wave’s threat by placing second in a Ford powered rear-engined car.
In 1965 it became obvious that the Offenhauser powered Indy roadster was finished. The race was dominated by rear-engined Ford powered cars. Only six of the 33 starters had front engines, and rear engines took the first four places, with Lotus Fords 1-2. Jim Clark and Lotus (on Firestones) finally won indy and relegated the outmoded Indy roadster to history.