unusual use for megasquirt - science project

[bobbarr]

I purchased a megasquirt kit from Glens Garage (v2.2). I need to help a kid with a science project. He wants to see if he can make a modified diesel engine out of one cylinder of a regular gasoline engine. Using an old Kawasaki motorcycle engine (twin cylinder 4-stroke), that has old fashioned breaker-points for the ignition. He wants to use the megasquirt to turn on a fuel injector from that input signal of the breaker-points opening (to negative ground). This will be on ONE cylinder only, at TDC (or perhaps a few degrees BTDC), and because he will be running at a constant load, constant RPM, all the other sensors normally going to a megasquirt will not be needed. The ignition fires every at every piston TDC, "wasting" a spark on the exhaust stroke.

1. I downloaded 225pi/release/sourcefiles.zip. Is this the correct bunch of files to unzip to run the megasquirt software to "tune" it on my pc? If so, what executible do I run on Windows XP? If this is not the correct zip file, which is the correct one to download?

2. Since I will only have one input (the breaker points opening) to megasquirt, will the software allow me to turn off all the other sensor inputs normally going to the megasquirt to run fuel injection, or do I have to simulate a voltage or resistance on the circuit board to fool the circuit board that these input sensors are "there"?

3. Will the software allow the megasquirt to fire the injector every 2 revolutions of the engine?

Any help to get us started would be helpful. Thanks.

[AR 67202]

what kind of injector will you use? Since a Diesel engine requires to inject into the cilinder directly, you need some pretty high fuel pressure. A common rail injector could do it, but those require more than 12v to fire... A gasoline injector will not do it. Is the compression ratio enough to heat the cilinder temps to ignite the diesel?

To inject only once per 2 revolutions is the easy part, choose 1 squirt/alternating, and only hook up only 1 injector channel.

Interesting project though...

[myk777]

I would set it up as a 2 cylinder engine, simultaneous 1 squirt, that's what I run on my single cylinder motorcycle engine (fuel only, stock ingnition is wasted spark), this gives you the proper RPM readings as well as one squirt for every two revs (one cycle for a 4-stroke)

Mike

[alienbush]

Diesel engines have about twice the compression of gasoline engines. I don't see how you could double the compression, and if you could, the engine would probably blow up because it wasn't designed for that much compression.

In concern of your safety, I would not try that.

[bobbarr]

I am trying to fire an injector on a twin cylinder, four-stroke motorcycle engine, BUT, I only want to fire an injector on one cylinder. Sounds crazy, I know, it's a kids science project.

The engine is a an old Kawasaki 400, which has old-fashioned breaker points that we will be using to fire the fuel injector on cylinder #2. I am assuming from reading the instructions on megasquirt that I will need to set the software to use 2 squirts, alternating so it will fire every other time. Because this engine uses a "wasted spark", I believe the way most motorcycle engines did it, it fires a spark even on the exhaust stroke of each cylinder, which I DON'T want. So it fires the spark every 360 degrees. I only want to have megasquirt fire the my one injector every 720 degrees, ON ONLY ONE CYLINDER.

Can I simply put a resistor in Bank #1 (or bank #2) to "waste" the firing of the "other" , non-existent injector which I will not be using so megasquirt does not overload? How do I know whether it's bank 1 or bank 2 that will be the one to fire? I believe that I need the cylinder that is NOT Kawasaki cylinder #1 TDC to fire, I believe it's cylinder #2, but I have to check the specs further.

How does megasquirt know which is the first (top dead cylinder of cylinder #1) firing of cylinder #1, and not the top dead center of cylinder #2? Does it not know, since this is a "wasted spark" application?

Any help would be greatly appreciated as we are trying to figure out this unique application and trying to figure out megasquirt at the same time.

[bobbarr]

Thanks for the advice. I have heard also to run it as alternating, twin cylinder. I wonder how I know which bank that megasquirt considers the first and second banks? I read in the help files that one can use a timing light, and then adjust the megasquirt software to tell it whether bank 1 or bank 2 will be tdc for a given cylinder, but there is not any specifics other than that one sentence about "using a timing light". Any uses had any experience with the timing light aspect with respect to megasquirt firing of bank 1 and bank 2 on the injectors?