Both are listed in the respective rules sections on the main page. They are the same with the only exception being that in RTR you get a bonus point for completing an incident free race.
RTR Points System...Changed to Nascars actual point system for Season 35.
And here is the MSR points.
- We are using a new points system. It will be 43 points to win, 42 for second, and so on down to 2 points for 42nd place. The winner will get 3 bonus points. Drivers will also get a bonus point for leading a lap and another bonus point for leading the most laps.