Yah, Harder the car is to drive, the more points you get. so lets say in first place driving the XFG you get 5 pts.. In the XRG you would get 10
Same with the Race3 server, you get more points for using the XFR or UFR than the FXR, XRR, or FZR in the GT2 class.
Lol, same with Race2, FXO is lowest, then RB4, then for highest points you would drive the XRT.