rusEFI: Open-source homebuilt fuel-injection set to rival Megasquirt

Electronic fuel-delivery and ignition controls have given us a new golden age of engine efficiency and performance. Most of us would never go back to the dark ages—say, before 1990—when you could still buy new vehicles with carburetors and clunky distributors. From the point of view of those of us who like to modify our cars, however, the black-box nature of engine-control computers limits our options for making changes to how our fuel-delivery and ignition systems function. You can get your factory ECU reprogrammed, you can buy an aftermarket ECU, or you can go down the well-traveled path of a non-open-source Megasquirt setup.

But what if you want to go open-source and install a custom ECU that gives you complete control over your engine's operation? Racer and software developer Andrey Belomutiskiy has been developing the rusEFI engine-control unit in his Chicago laboratory, and he now has a rig that can control an engine well enough to start and drive a car.

Right now, the rusEFI unit consists of a custom printed-circuit board (known as "Frankenstein") made to work with an off-the-shelf STM32F4 Discovery board. Add a power supply, a chassis and a harness connector, and it's ready to replace your factory ECU.

Well, almost ready. At this point, the rusEFI uses MAF sensor and throttle-position sensor data to control the engine, which means the finer points of acceleration enrichment, exhaust-oxygen feedback and so forth haven't been implemented. Much code still needs to be written or adapted, more sensors need to be connected to the ECU and more developers are needed to move this project from the experimental realm to something that an ordinary car guy could use to control his octo-turbocharged Studebaker 289 engine.

I have verified with my own eyes that the rusEFI actually works. Andrey plugged it into the engine harness of the Team We Are Not Really From Iran Ford Festiva—which features a wild Mazda B engine swap—at last weekend's 24 Hours of LeMons race in Michigan, and the car drove happily around the paddock. Currently, rusEFI can control spark timing, fuel injection and the fuel pump, and it has functioning data logging and USB connectivity. It is compatible with the popular Tunerstudio tuning application, the same one used by most Megasquirt tuners.

The rusEFI ECU is an exciting development for those of us who want to use modern engine controls in our weird car projects. Things will get very interesting once it can work with more engine sensors and tuning applications. Check out the Kickstarter if you'd like to buy into the project and reserve a Frankenstein board. Also stop by the wiki and forum for more information.

By Murilee Martin