motorherp, why are you planning on making a new game from scratch, instead of modding an existing game?
That way, the basis for your work would be already laid down, giving you the chance to concentrate on what's important (imo): car physics and car modeling. Many games have open codes and there's already an established knowledge base.
I ask this because, after playing GP4, I became (and still am) totally addicted on a F1C 99-02 mod. After a little playing of the original game, which I found that had awful physics, bad modeled cars (too long) and tracks, I understood the development scope that the game allowed when I started playing the "Prototype-C" mod. This mod feels a lot more real than GP4, with the advantage of having to cope with the limitations of early 90's group C cars (almost F1 engines, but lack of front downforce) and endurance racing issues (the need to drive smoothly and revving moderately). The physics were developed with the cooperation of Michael Fuller, from "Mulsanne's Corner" (
http://www.mulsannescorner.com/) and jumping from car to car is to discover very different and realistic handlings.
You can check it at
http://www.virtua-lm.com/ and sorry if it seems I'm advertising, I'm hooked on it for some months now...
And more: if, at least, you start with a mod, it can be easier to "beta-test" and get feedback from the basic aspects of your game (many people have a single game and multi-mods in their HD). Later, you can take that development and apply it in a stand alone game. Simbin did it before the GT-R game was conceived.