Car remapping, also known as chip tuning or engine tuning, is the process of modifying the software or firmware that controls the engine of a car. The aim is to improve the car's performance, usually by increasing power and torque output. In this process, a remapping specialist will modify the engine's ECU (Engine Control Unit) to optimize various factors such as fuel delivery, ignition timing, and turbo boost pressure. The end result is a car that performs better than its stock version. However, it's important to note that car remapping can affect the car's warranty.