Hitting the upgrade button will take you through to upgrade screen. Some upgrades will take time to complete, you can skip the timer using Gold.
Here you can upgrade aspects of your car for cash, upgrading each attribute will grant the following and increase the overall Performance Points (PP) for the car:
- Intake - increases your overall Power
- Exhaust - increases your overall Power
- Engine - increases your overall Power
- Nitrous - increases your overall Nitro
- Gearbox - increases your overall Power
- Tires - increases your Handling and Traction