In the Garage Menu or in the car selection screen, tap on the UPGRADE icon in the lower part of the screen. The game will display the car stats and the available upgrades. There are 4 categories of upgrades: Acceleration, Top Speed, Handling and Nitro. Just tap on the icon to buy the upgrade of the desired category. There are 5 steps of upgrade per category.
How do I upgrade a car?
Last Updated: 498d