Complex sentence: Fury was never able to haul in Francevic's early points lead and Francevic was crowned champion, but left the team shortly afterwards, returning to the Mark Petch team as they began development of a Ford Sierra turbo.
Split into simpler sentences: Fury was never able to haul in Francevic's early points lead and Francevic was crowned champion. He then returned to the Mark Petch team as they began development of a Ford Sierra turbo.