 Complete the following phrase:  Cooper travelled down to the 1960 Argentine Grand Prix seemingly at the peak of their powers, and Trintigt won the Buenos Aires F1 event that preceded the main championship race. However this turned out to be the last major win for a T51, as the speed of the new Lotus 18 began to dominate. On the journey back, John Cooper made his mind up that to stay at the front he needed to build a new car, and at the next championship race at 