Since you are looking for the best features of the in Assetto Corsa , you are almost certainly looking at the legendary release by the RSS (Race Sim Studio) team, specifically found within the RSS Formula Hybrid 1984 pack.
A car mod alone doesn't create the 1984 experience. To truly step back in time, you need to pair the ASR cars with specific environment and utility mods. assetto corsa f1 1984 mod best