PSAT is based on a maximum score of 1520, SAT on 1600, so it is expected there would be a <100 point bump all other things being equal.
All this gamesmanship with the SAT and ACT by applicants is nonsense. Take it once, there's your score. If you take it 8 times over two years you haven't earned a higher score and it doesn't make you any smarter relative to your peers - you just figured out how to game the system. There should be some kind of descending weight applied to your score every time you take the test again - the more times you take it, the more the score should be discounted, because if you take it multiple times and there is no increase in score, then that says a lot.