It was mainly how to do the actual race, but I think I've got something after reading through the Savage Worlds rules.
Savage Worlds has the Chase rules, I feel I can probably straight up use those with little in the way of modification. The idea is to have each lap as a Chase in their own right, perhaps cutting to 'behind the scenes' stuff in between each lap as the other players (if they're not in the race) do stuff.