Someone has made a tool for the PC Version of Dirt 3 that reduces the grip to whatever you choose, I have founf 85% is the sweet spot, which makes the cars handle much more realistically. You now have to employ real life rally techniques like turning in early and countersteering, the rear end is much more satisfying like this. Definitely worth trying out if you are like me and think there is too much grip in tthe default game. 
 
Link: http://www.dirt2-tools.110mb.com/download.html 
 
It's the first download. It has a button that lets you return the grip levels to default so you can play multiplayer easier. I've found you need to knock down the difficullty a bit, I've been having competitive rally stages on 3 when I normally play at  or 5. Rally cross the AI dn't seem to be as fast, 4 is fine for me with them.