TORCS - The Open Racing Car Simulator, is a famous, exciting and open source driving car simulator game. TORCS has great features, including licensed cars of various types from NASCAR to Formula 1 and normal sports cars. There are also many different tracks, many different options to choose from and even the ability to make your own cars and tracks.
When you first load up the game, you will find many options to choose, for example, you will be able to choose which racing modes you desire to play, quick race, non-championship race, endurance race, championship, challenge race and practice. You will also be able to pick the type of car you want to race with. By default there are 50 cars to choose from, some better looking than others. There are road tracks, dirt tracks and oval tracks to choose from.
TORCS manages great 3D graphics, you will find a lot of different camera views, nice lighting effects, smoke, skid marks, car damage and some more. You will be able to see it all if you set it up in the options menu.
To sum up, TORCS is probably one of the best racing car simulators, and one of the best features, it's totally free.