Complex sentence: Further development in 1975, including a 6 speed gearbox-a novelty for the time, helped Fittipaldi and McLaren to second in both championships, before Fittipaldi in a shock decision left the team to join his brother's Copersucar team.
Split into simpler sentences: Further development in 1975, including a 6 speed gearbox-a novelty for the time, helped Fittipaldi and McLaren to second in both championships. At the end of 1975 Fittipaldi, in a shock decision left the team to join his brother's Copersucar team.