By chip tuning or remapping your MG, you will experience better overall driving performance through adjustments in ignition timing, fueling, air intake, and other factors that can be customized to fit your driving environment and style.
Chip tuning is the method used on vehicles manufactured before 2000. It involves removing the Engine Control Unit (ECU) from the MG - a relatively simple procedure - and then removing an EPROM chip from the unit to "read" the generic data stored on it at the factory. EPROM stands for "erasable programmable read-only memory" and refers to the kind of memory that retains information even once its power supply is turned off. Manufacturers use generic values on these chips, so you can achieve higher performance by having the data on the chip altered to fit your circumstances. Once the chip has been reprogrammed with the appropriate values, it is reinstalled into the ECU, and the ECU is put back into your vehicle.
Remapping is the same as chip tuning, only there is no need to remove the ECU from the car because the stored data is read data is read via an OBD/OBDII port to connect to the electronic on-board diagnostics in your MG. This procedure is used on new vehicles dating after 2000 that have these diagnostic capabilities.
The performance gains are the same whether you apply chip tuning of ECU remapping. You will enjoy a more powerful drive, better fuel economy, and a more responsive throttle after the procedure.