If you want to unlock all Prototype parts, get 1,500 respect points from all CPU characters. Moreover, it's possible to unlock the Bronze, Silver, and Gold Prototype Challenge Series! Just complete all series in Arcade mode.
Go to the test track when you are in your Corvette Z06 and drive backward. Near the curb with the crane you will see dirty place, now drive into it. The dirt will harden, so you will be able to drive onto it. Somewhere in the middle of this "track" drive off to start bouncing. Note: your car will be damaged!
In the game, you can make your car fly. First, get a tuned Viper GTS and go to the oval track, you should drive about 210 mph. Turn into a wire fence when it's time to turn to the other side. Hold the nitrous while making this turn to fly. Note that you must hit the nitrous several seconds before you make this maneuver to get the desired effect.
Earn easy respect points, first! Call any character on the mobile phone, then get pink slips for the race using one of your worse cars. Sell the car after you reached the place of destination. You will have extra money, but be sure that you have more than one car because you can fail in the race.