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.