Corners...
	Money without using energy/IAP...
	Nudging Opponents...
	Off-Road Handling...
	Unlock Secret Levels...
	Various Game Hints...

To clock the best times on the track you must be steering out of a corner almost as soon as you get into it.

Go to an elimination race but instead of destroying the other cars, just drift. Let the others go first and wait 5-15 seconds then go around the track and drift for as long as possible. There is no time limit as long as the other cars are intact. If you can drift well, a few minutes can net araund 1.5 K.

It is not illegal to nudge your opponents off the track to slow them down. You can completely take your opponent out of some of the races by nudging them over cliffs.

You can take a much more experimental line through the corners without worrying about crashing so much when your car has fully upgraded off-road handling.

Search for a shining box in a racing map thats places outside the normal race zone to unlock a secret level. There are 3 in the tropical and 4 in the jungle. These boxes will not appear twice on a same map (not race).

You should be steering out of a corner almost as soon as you get into it if you want to clock the best times.
Don't be afraid to nudge your opponents off the track. Some even have cliffs you can push them over.
With a car with fully upgraded off-road handling, you can take a much more experimental line through the corners.