according to Richard Hammond, the Ford Sierra, Cosworth edition, is the winningest car model ever raced, winning 84% of it's races

that answers a question I asked once, what was the winningest car ever.

By the way, it was so impressive, that it became the most stolen car in England, and - insurance companies refused to insure it, because it was utterly shit about locks and security, and thieves could get into one with a screwdriver, then couldn't be caught by cops