How to make a race car

Hello! Recently, I've been working on a small vehicle simulator for someone. Everything is going over well, and I used [this][1] great guide to make my vehicle not flip over, etc. The only problem now is that the vehicle I need must go fast, which I can already do, but it slips/drifts too much. I currently have all slip values set to 0.001 (lowest possible value) and hardness values set to 1. What I am aiming for is something like cars in the Asphalt series, which can go fast without losic control, except not necessarily that fast. Any advice will be greatly appreciated. [1]: http://forum.unity3d.com/threads/how-to-make-a-physically-real-stable-car-with-wheelcolliders.50643/