Boost
Hold [Select] while choosing an area selection
at the map screen. Release [Select] when the auto-pilot engages.
Start a race, and you will be able to use a boost. Note: This
can only be done with cars that do not already have a turbo.
Foggy weather
Select time attack, free run, or vs. battle mode and
choose rain. Hold [L2] while you are selecting the track
starting point to make it foggy.
Snowy weather
Select time attack, free run, or vs. battle mode and
choose rain. Hold [L1] while you are selecting the track
starting point to make it snow.
Stormy weather
Select time attack, free run, or vs. battle mode and
choose rain. Hold [R2] while you are selecting the track
starting point to make it thunder.
Switch engines
Get over 1242.8 miles (2000 km) on the odometer on
a car to unlock the ability to switch engines on that specific
car. Successfully complete 100% of the game to switch the engine
of any car.