Problem with performance

As I am an old player (44 years), I don't necessarily have time to find all the settings to make a race.

So I play in rookie mode and I don't understand the performance of the cars from one year to the next.
if I take the 1996 mod, I can start last and overtake everyone in one turn. on the other hand if I take the mod 2008, I turn 5 to 6 seconds slower than everyone else. if I play multiplayer (I like to take several drivers) when the computer drives them, it drives faster than if it is me who drives them

how does that happen? Are there any files that need to be processed? same things for speeds, even if the performance file indicates 7 speeds, the game only uses6!!


Can you help me?