Get over 50 points in the Dyno Run1 mini-game to unlock the Drivetrain bonus upgrade.

Get over 100 points in the Nitrous Tuning 1 mini-game to unlock the Engine bonus upgrade.

Get over 100 points in the Dyno Run2 mini-game to unlock the Suspension bonus upgrade.

Get over 150 points in the Nitrous Tuning 2 mini-game to unlock the Turbo bonus upgrade.

Get over 175 points in the Nitrous Tuning 3 mini-game to unlock the Nitrous bonus upgrade.

Get over 2,000 points in the Engine Tuning 1 mini-game to unlock the Exhaust bonus upgrade.

Get over 4,000 points in the Engine Tuning 2 mini-game to unlock the Wheels bonus upgrade.

Get over 5,000 points in the Pressure Tuning 1 mini-game to unlock the Chassis bonus upgrade.

Get over 5,000 points in the Engine Tuning 3 mini-game to unlock the Controls bonus upgrade.

Get over 7,500 points in the Pressure Tuning 2 mini-game to unlock the Brakes bonus upgrade.

If you crash your car in a race and you have a manual transmission, put it in neutral. Hit the gas all the way, then slam it into first gear to get a very quick boost.