This track was Grattan, its near Grand Rapids In MI, and a-d groups all go out as their own group. Example: All the a group drivers are out on track at a time, then they come off and then all the b's go out. You can only pass by getting a point from the car infront of you, they dont have to let you by but if your right on their ass they aren't going to drive as well. So basically you should let them pass unless you want to be an ass.