Old cars with no rear wing generally has very loose rear end, including rear wheel drive. This is correct behaviour For acc, If you select aggressive setup in Acc, cars rear end is very loose, for example, Porsche cup car. I have compared acc and raceroom for Mclaren 650gt3 with force feedback off in silverstone. Both car has very similar handling characteristics. for lift off oversteer. Toyota mr2 is famous for that. Please watch the video below near the end. You need to use left foot braking
Apples and oranges. I'm sure a Scirocco (FWD, front engine) is the same to you as a Toyota MR2 (RWD, rear/mid engine), but it's really not. Neither is a Porsche. Also I've never said the car behaviours in both games are TOTALLY DIFFERENT and RR is bad or ACC is best. I said ACC feels a tad better. That is all. I get it. Game is perfect. Don't criticize.