I'm afraid that such complex setups are almost entirely up to the physics capabilities in Unity. If you can configure all these suspension parts using Unity joints, even using a solid wheel for the initial draft, then both EVP and VPP should be able to work with it. A simulation like this will require a physics update rate of at least 100 Hz, most likely 200 because of the size of the cars.
Of course, if you're targeting such realism then VPP fits much better. EVP doesn't apply the tire and suspension forces necessarily at the tire contact point, but both wheel forces and application points are tweaked for gameplay based on the EVP controller settings.
VPP simulates realistic tire contact, tire forces, and vertical spring-damper suspension. If you're using joints for suspensions, then VPP suspension may be configured as the tire stiffness. VPP wheel colliders may then be attached to a wheel hub represented by a Rigidbody that is attached to the chasis using the RC suspension set up with Unity joints. When this hub moves, the angle of the VPP wheel collider will change providing camber and caster effects.
There are other effects characteristic of RC cars that are not simulated neither in VPP nor in stock Unity physics, and would require additional development to be addressed realistically. Some of these are:
- Variable tire radius and friction properties based on the RPM of the wheels. As you know, real RC wheels change both their shape and radius with more RPM.
- Modify the angular momentum of the car depending on the acceleration of the wheels. This is typically used to balance the cars while in air.
- Specific effects of driving over loose surfaces such as dirt or mud.