ModNation Racers: Boost at the Start of a Race
In ModNation Racers for the PS3, you can get a boost at the beginning of any race.
To get the boost at the beginning of the race, click and hold L1 right as the announcer says GO after doing the 3, 2, 1 count down.
A trick you can do that may help is to press the PS button when the announcer is counting down, which will pause the game right when you need to press the L1 button for your boost. Resume your game and hold L1 to get your boost.