They had big success in 1963 with the Lotus 25. With Jim Clark driving, Lotus its first F1 World Constructors Championship. Clark was killed in a crash in a Formula Two Lotus 48 in April 1968. It was a severe blow to the team and to Formula One. Clark was the dominant driver with the best car at the time. He is an important part of Lotus' early years. The 1963 championship was won by Clark's teammate, Graham Hill.