Max out all Performance Points on a car. 10
Performance points are earned by coming in 1st, 2nd or 3rd place in a career race. You get 1 point for each amateur cup race, 2 for the pro cup races, and 3 for each paramount cup race. If you are a good driver you should have your car maxed out near the end of the Amateur Cup.
This just is not true. I made all the way first places through amateur cup and halfway through pro cup and only got 7 upgrade points so far. They seem to either drop randomly, or there must be any other special requirement to earn upgrade points. You need about 50 or so alltogether, earning them in one amateur cup is not possible.
EDIT: Start getting those performance points since mid of the pro cup. first got 1 point now starting getting 2 points for first place. Increasing like this, should be maxxed out pretty quickly. This game is easy and rocks!