Finish all 10 races in the quickest time possible. Position is very important, good positions are rewarded well. 1st position will be given an upgrade, 2nd position will allow you to proceed to the next level without upgrades. If you finish 3rd you will have to restart the race, this time will be added to your overall time. Avoid this at all cost, this is the biggest time penalty.
Upgrades include speed, acceleration and steering. You will need to try different combinations to suite your style to win the game.