I would look at Runtime/InputDevice, Runtime/InputCore, and Plugins/OculusRift. Also at Logitech’s SDK, of course. Fanatec’s SDK might be less mature, and they’re less common (because while fantastic wheels, they’re relatively expensive). I’d aim for rolling your own API as a wrapper of Logitech’s SDK and then modifying your API to call either Logitech’s or Fanatec’s. Good luck with your project, the world could always use more racing games!