You can adjust the handling of the car with the diffs. You don't really want to run them too loose but you and adjust the steering by running them a little on the tight side. And if you're running a locked front diff, you should run the rear a little looser to help witht the low speed steering. Running a tighter front diff will give you more pull off the corner. They tell you that in the manual so you don't run it so loose that you're going to let it slip. In a TC, a slipping diff is a bad thing.
