What are Performance Boosts?
Performance boosts increase the traction, horsepower, and gearing of your car in order to improve its elapsed time. Performance boosts are bought on a car-by-car basis and are purchased in 5 or 10 run packages. The performance boost is used automatically once purchased so you don't need to hit any buttons to activate your performance boosts.
How do they work?
A performance boost will automatically add 10% more horsepower and traction to your car, as well as modifying the final forward gear in your transmission to be longer. A longer gear means all your new horsepower won't cause your car to redline and cause damage in the final forward gear. Once all your performance boosts are used up, the car will automatically lose that 10% power, traction, and gear modification and you'll have your old car back.
Since the performance boosts are bought for a specific car, they are perfect if you find yourself struggling to beat that last career mode tournament or a tough opponent in multiplayer. There's no limit to the number of times you can buy a performance boost for any car. Performance boosts also never expire. If you buy performance boosts and then don't use that car for days, weeks, or even months, the remaining boosts will still be there when you're ready to race again. Performance boosts are purchased with coins, so if you need more coins you can click the green plus "+" sign in the top right of your screen and buy more coins.