The online challenges are amazing btw, the fifth one gives you a million dollars and 100,000 points, for about 10 minutes of driving.
Found out something else that was intresting though, i sent my bob out in a skyline gtr spec v at the daytona race in the "wind" challenge in extreme series cause after i gave it an oil change it had too much power for me to use it in the race i was talking about above so i want some miles on it to bring the power down by a couple of hp's, and of course it finished dead last, BUT i earned 34,000 credits and 8,000 b spec points, by contrast my formula one car in the same race wins and i receive about 80,000 and 8,600 b spec points. the only thing that i can think of is that the points are proportional to the speed of the car, but if your only looking for points, which a lot of us are, that should mean that you can just throw in a really bad car and let it loose and you will prob get almost the same amount of points as if you would have won with a really fast car.