Hi,
Tricky indeed. basically you should understand that a free floating object does drift very much like an object in water or in space, so you might requiere some fine tuning.
You should approach this as a plane with a magnetic link with the track. so cut down the problem.
--- can you fly a plane realistically?
1: have a box, and a camera following the box. can you have the box give the feeling of fyling like a plane, as you move up and down, left and right?
2: can you have this box flying in an environment? sometimes the environment is too small or too big, so you'll need to ajdust the physics and forces for the plane to fly realistically within the various props
-- can you make a box follow a plane based on a distance?
1: try to constraint a free floating physics box so that it's always within a certain distance of the plane surface ( hint: use raycast to find the distance between the box and the plane, and apply force based on that distance)
2: now, try to push it and have your system counter your action so that it tries to keep it at this distance exactly, you will have some bouncing around and stuff.
-- Now combine both, you should be pretty close to a wipe out type of vehicle.
keep at it, this is far from being the easiest behavior to reproduce.
bye,
Jean