What cars would be competetive in that MG ? Fastest car I have at the moment is a fully modified Ferrari 458 Italia…
Preferably a Le Mans car, the maximum PP you’re allowed is 700PP (any car which is over you can add ballast to). Keep an eye on the used car dealership as that is where all the rare cars are, this used car dealership search will help you find out how many in game days you must wait before your desired car appears. As Dizzy said, focus on the seasonal events, that’s where all the big money is.