There really isn't too too much of a learning curve if you've got an FFB setup that is, or is nearly maxed. I'd just say learn with the S-Chassis SP cars, and start with a medium HP car, around 500hp, and keep the full 60 lock. Overall SP is much more sensitive, so you've gotta tame yourself and get used to hard throw-ins.

That said, you may want to re-install SP just to ensure it isn't bugged out. When I first installed everything as a bundle, PD was fine but SP behaved like no car I'd ever driven and was absolutely horrible lol. After re-installing just the mod it was much easier . No idea if it will apply for you, but good luck! If you see me in-game again, feel free to ask for my setup as it could also help a bit.