This tip keeps you in the millions,, you need a fast car and a steering wheel with pedals, in my example I use the escudo Pikes Peak version (won from finishing all the rally races). Once you have the car and the steering wheel. You go to the endurance races and choose the last one (test track 150) start the race put something heavy on the gas pedal and turn the wheel to the right and walk away for 53 min. The car will ride the wall the whole time, dont worry about the tires on this car its still fast, when you get back you've got 200,000CR and a new car! works every time!