I think what he's after is a list of cars for each event that
a) Does not appear as an AI-entrant
b) Does not blow away the competition
c) Is not too inferior to the competition
For instance, a Mazda RX-7 for the El Capitan 200 race. It's not among the possible AI-cars for that event, it won't blow away the AI, but it's not all that hard to win with it either.