Setting up a remote control car is as much a science as it is an art, the physics behind rc cars is exactly the same as the physics that governs real cars, if you know how setup changes in a race car work, you already know how to setup a remote control car.
The problem that most people have with setting up RC cars is that when you make a change in one area it always has a knock-on effect on the rest of your settings, setups are very much a balancing act
To start with I’ll concentrate on the basics of handling, over steer and under steer. The physics behind this is pretty simple, if you turn into a corner the center of gravity will move in what ever direction you were initially travelling. Your tires via friction push back with (hopefully) an equal amount of force. When your wheels lose traction and start to slide the energy that was being turned into heat in your tires gets released as inertial energy in the original direction of travel. With cars, both back and front don’t break traction equally, this creates either under steer or over steer, which is how we describe the experience the driver has under these conditions.