DIY 30$ electronic fuel injection

I've been working in this for the past month or so. It took quite some tinkering to figure it all out, but now it's working.
For the controller I'm using an arduino uno with the ardeums328 firmware. This is a variation of a variation of the old mega squirt 1. https://sourceforge.net/projects/arduems/   It only works with a alpha n fueling algorithm, which is ok for a governed Briggs engine. For the intake manifold and throttle body i used an old manifold from a Briggs with a hol drilled and tapped to M12 thread (I'm from Germany ). Then I put a bolt in my lathe an drilled out the inside for the injector. The injector is hold in with lock tire and the threaded in the manifold. The throttle body is from a 1.2 liter Nissan with all the springs removed and cut down to size. Mathe o2 sensor is just a Standard Bosch part from the scrapyard. For the rpm pickup I used the killwire from the ignition coil with a 100k potentiometer as a voltage divider to ground. His is not enough to kill the spark, but enough for a signal to my ecu. As temperature sensors I used what I found. I had to make a shield for the arduino with the voltage dividers for temperature battery volts and signal conditioning. The gas tank is just a "redneck gas can". Look it up on YouTube and you will se a guide. Now I finally got it running, but still need to do some tuning.

https://youtu.be/VnAtMlOD_hw    Sorry for the crappy video. I will make a complete tour soon.

Looks interesting. There are a lot of possibilities if your really into computer stuff. What kind of fuel pump are you using and roughly what pressure? I linked your video so people could see a preview of it. If you click the youtube button on top of the posting box you can insert videos like this. Welcome to atltf!

Thanks for linking the video video the right way mr.modified. I'm new, so I didn't now.
The fuel pump is a random part from the scrapyard. I pay per poun, so a fuel pump is cheap. The fuel pressure is 43 psi with some random regulator from the scrapyard. I just used hose and hoseclamps for a standard two line fuel system.
Right now I'm changing some of the programm for better tunability with tuner studio.

I guess with fuel injection, supercharging or turbo would be easier than with a carburated setup. Nice if you can figure out the computer stuff, you could play around with automotive computers at some point.

The engine is using the throttle position and rpm and not vacuum and rpm wich you need for turbo or supercharging it. I might just buy an arduino mega for 10$ some day and use map with it. My current controller doesn't support a map sensor.
The main problem with an automotive ecu is that it's made for one specific engine, and can't be custom tuned. Also the pin mapping would be fun.

I just tried it out this afternoon, but it's still running rich on wot. I will have to take small steps until I can drive it. Then it will be tuning on the go. Tonight I'm gonna build an adapter for for my laptop to hock it up to 12v. I also have to figure something out about my key switch. It currently has the contact for the starter relay bind up, so I have to turn the ignition completely off and on for the contacts to loosen up.


Still work to be done, but getting there.