Every race is different in Ignite. Each race brings something new as players try to win by using their own tactics during the race. The player chooses the track, the car and the car configuration. The type of car defines how the car will handle for instance muscle car tend to drift better while race cars have a higher max speed. The race configuration adds bonuses to some actions for example to +30% drift bonus.
During the race the players may try to hit objects, drift or draft behind others to gather score. If they gathered at least 1000 score they may start using nitro.
At the end of the race when all players crossed the finish line, all left over score is converted to time bonus. For each 1000 score gathered the players receive 1 second deduction from his total race time. If a player’s time gets better with the time bonus deduction than some other player’s time he gets in front of the other in position.
Source: The Developer Website.