Hold L1 + L2 + R1 + R2 while selecting a track. You should see headlights appear
in front of the car. A new symbol will appear to confirm.
Pause the game and enter the "Sound" option. Highlight "FX Volume" and
press L1 + L2.
Upside down tracks:
At the track selection screen, press L1 + R1 + X + Down. A new symbol will appear
At the track selection screen for a two-player battle, press X + Square + Triangle
+ Circle. A new symbol will appear to confirm.
At the start of a multi-player race (during the countdown), press Circle + Left.
Night Time Mode 800a6d0c0001
Race Upside Down 800a6e280001
Thanks to Revolution readers Miranda March, David Cox, Booster, and Jose Antonio