I’ve heard plenty of talk on various forums to the effect of “I’d use this car/setup on a track that doesn’t require aero parts, and this car/setup on tracks that do”, etc etc. Does anyone know of or would be willing to create a list of which tracks fall into either of these categories?
If you’re racing anything past D class, then the car will more than likely have aero on it simply to reduce the PI, but the settings will be minimum because it doesn’t need the extra handling for how slow it goes. On La Sarthe, never use Forza aero. On the Nurburgring, cars start using aero around B class or so. You can always view the leaderboards to see what upgrades people use on a track in a particular class, but it’s also fun to experiment and create competitive cars yourself! For example, 99% of people in S class use Forza aero, but a guy I know got me hooked on the Ferrari 458 with no aero upgrades. It dominates lobbies and has even set some top 200 times. In short, if you think a car needs or will be faster with aero, by all means test it and use it (or don’t if that’s better for you).