How do you access bonus cars on nedd for speed undercover

Go to Quick Race, then click to go to the Event Map (don't go to My Cars). Select an event first, then the game will ask you to pick a car. When it does, just scroll over till you see the "Bonus Cars" section; all the cars that you entered cheats for will be in there. Or if you have unlocked tier 1 cars go to my cars and trick out the Bugatti. then do what he said