Quote Originally Posted by Mark
How many seasons have seen a team fielding a world champion in both of their cars?
1967 saw Clark and Graham Hill line up for Team Lotus; this continued for the first race in 1968. Prost and Senna raced for McLaren in 1989. Farina and Ascari both raced Ferraris in 1953. There may be other instances of one off races particularly at Ferrari, but these are the three seasons that come to mind.