Instructions
Purchase a fast car. Any car from Tier 3 will work, most notably the SLR McLaren. Purchase cars from the "Shop" menu using the money you earn from winning races and selling your old cars.
Learn the shortcuts for the tracks you will be racing on. These tracks are "Desperation Ridge," "Lucky Tower" and "Eternity Ridge." You may select these tracks in "Free Race" from the main menu to practice and learn the various shortcuts scattered about on each track.
Race cleanly. Do not ram into your opponents or any walls, and don't lose control of your car. The final bosses will capitalize on any mistakes you make and take that opportunity to pass you by; it will be difficult to pass them back because of their skill.
Apply the brake lightly into every corner to maintain control of your car. Apply the gas halfway into the turn to resume your previous speed. This allows you to stay in front of the bosses.