 Complete the following phrase:  As soon as the car and the engine became reliable, the era of the Lotus and of Jim Clark began. Clark won the title twice in three years, and , the latter being the only occasion to date of a driver winning both the Championship and the Indianapolis 500-Mile Race in the same year. For 1964 Lotus introduced the new Lotus 33 and Ferrari made considerable technological and ficial effort to win the title. Ferrari used no less than three different engines in the seasonthe existing V6, a V8 and a flat-12, while Lotus was struggling with the teething troubles of a new car. The title went to John Surtees and Ferrari. Surtees title was especially notable, as he became the only driver ever to win the World Championship for both cars and motorcycles. The 