The sim is open source, i.e. the code is open to the gaming community for customization, modding, etc. Sky’s the limit.
Image Space, the company that made the game is pretty big in the sim world. They did a lot of EA’s sim games (F12000, Sports Car GT, etc. etc.) for EA before they got sick of EA’s tactics and told them to shove it.
If you ever check out some of the sites like the US Pits, Sports Car GT, EA Nascar 200x, etc. were big in the sim world for modability. People took the physics engine (which was awesome), and added new cars, tracks, etc and basically extended the life of the game 10x over. Touring cars, Australian V8 cars, LeMans style cars, tracks like The Ring (not spelling it), Brands Hatch, etc. etc. were all made for these games.