Can you get away with running a modified engine on a stock ECU and fuel injection system? It depends on the type of modification. For most engines, the stock ECU and fuel injectors will be sufficient. However, in the case of engines equipped with an aftermarket turbocharger or supercharger, standard fuel injectors will reduce performance, as they will not be able to keep up. As younger generations of engine manufacturers, pilots and automotive enthusiasts continue to show their affinity for EFI and tuning, and more and more older generations are looking to learn modern tuning techniques, the ECU in their vehicle has become increasingly important. By adjusting the ECU, you're trying to optimize your vehicle so that it works at its best: adjusting the ECU improves overall performance, fuel economy and vehicle power.
An aftermarket adjustment or a ready-to-use one is likely to be the best option if your vehicle is heavily modified. And to complicate matters, you'll get similar results with a standard ECU adjustment or with an aftermarket ECU adjustment. To do this, a replacement or ready-to-use ECU has been designed from scratch and does not take into account the factory settings, giving you full control over the engine setting. Adjusting or reflashing the factory ECU is a technique in which software packages are used to adjust the ECU in a similar way to the factory one after a modification. In conclusion, it is possible to tune an engine with a stock ECU and fuel injection system. However, depending on the type of modification, it may be necessary to use an aftermarket adjustment or ready-to-use ECU in order to get optimal performance.
Additionally, reflashing the factory ECU is also an option for those looking to adjust their engine settings.