Could be an issue with the (open?) diff, but feels to me like it's more than that. If you compare the Copa A / Copa B / HotCars version of the Passat, it's like night and day. The Coba B version is underpowered yet slides all over the place on corner entry and has nasty on-throttle understeer. Any kind of braking under cornering or weight transfer will send you into a tankslapper. Almost like it's on road tyres or semi-slicks, or the suspension is somehow broken. The HotCars version is actually very raceable with lots of grip. You can stomp on the brakes in a straight line and it will stop on a dime, you can induce some mild oversteer to turn in and then modulate the throttle to get a good exit. Typical FWD stuff. On a relatively flat track like Taruma, you can pretty much drive like the real drivers do on the video. No tankslappers, no uncontrollable drifting, just powering out of corners. You can still make it drift but this is easy to control by application of the throttle. But HotCars is the 80s' version of the car, whereas the Copa A/B is a modern version? I would have guessed the old version would be much harder to control. It's possible the diff is different between these version, but would be surprised if that's the only thing. This is why I wanted to know what the precise difference between these versions is, because if they can make HC version drive well I see no reason why the Copa Classic versions couldn't be nice too.