homerlvsbeer, Just do the same procedure and just look for the forcefeedback folder of your Dirt 3 game and replaced the files. Although I haven't tried it, I'm sure it will work. I am installing now my Dirt 3 game and would definitely try it.
I installed Dirt 2 and copied the forcefeedback\effectsetup from it and paste it on Dirt Rally forcefeedback folder. There was definitely an improvement and much better handling and I am using only a gamepad. It will not affect the game itself and I did not experience any PC crashes or hanging. You can feel now the weight of the wheel when you are driving. Just make a backup of your file in case you decide to put back the original files.