ECU Tuning is a way of optimising engine performance software stored within a vehicles Engine Control Unit (ECU). As engines have become more advanced to meet emissions standards, so have their control units and the processing power within. There are many parameters which can be altered within the software of an ECU to optimise engine performance whilst remaining within engine design limits.
There are several uses for a more powerful vehicle during day to day use. Some owners may require more power for safe overtaking manoeuvres. Others may need more power when towing heavy trailers or caravans. Some drivers may simply want to upgrade their vehicle without the need to buy a new car.
How does a remap increase power?
The main power increase from a remap is the result of injecting more diesel into the engine when the driver requests full power. Alongside the increased level of fuel flow, there are other considerations:
Injection Timing – It is important to calculate the optimum start to the injection period. As there is an increased fuel flow entering each cylinder, the time at which it begins must be sooner to ensure that it can burn completely before the exhaust stroke.
Fuel Pressure – A small increase in fuel pressure yields two main benefits: The first being better atomisation of fuel, this promotes a more efficient burn, resulting in more efficient use of the fuel injected. The second benefit to a small increase in fuel pressure is that the length of the injection period will be slightly reduced. This allows for a greater flow of fuel to enter an engine in a time period whilst ensuring it can be burnt completely before the exhaust stroke.
Turbo pressure – Where applicable, turbo pressure is increased to give a greater mass flow of air into the engine. This means that more fuel can be burnt whilst staying within stoiciometric requirements, resulting in increased power output.
It is important to note that not all of the vehicles we tune have electronic control of the turbo charger. As an example, the much older 2.0 HDI 90 engines have no electronic turbo control. This means that we set up the stage 1 remap to use the ‘spare’ air available without requiring an increase in boost pressure.
