[Won24]

Hello,

I am attempting to make a diesel engine engine utilize a supplemental fuel (E85) during normal operations. I am going to use this stand alone ECU https://controls.is/shop/ecu/DID1 since it already has a base map for running the engine I intend to use. I talked to the developer of the ECU and he doesn't seem to think it will support the additional six fuel injectors due to hardware limitations and recommended I used another one of his ECUs to do what I want. He said his ECUs could communicate over CAN bus. Which I would imagine I could do with the Speeduino instead of buying two standalone ECUs. Or should I say stand together ECUs? Regardless, that leads me to why I am here.

I somewhat doubt Speeduino could be used to run the diesel alone. That seems like a large undertaking which is not the intent of the project. Can I use CAN from the main ECU to create a piggyback Speeduino system of sorts which will give me the ability to drive six more injectors? I would also like to be able to vary timing and amount of fueling based on knock, so that would likely require some communication between Baldur's ECU and the Speeduino. Curious to hear folk's thoughts.

The target engine is a Mercedes OM648, 3.2L straight six piezo injector common rail turbo diesel.

[DStage]

Just out of curiosity - how are going to inject E85? Straight to the manifold? If so then do you need sequential injection / control over each injector individually? maybe it would be sufficient to have them in pairs and use simpler set-up. I'm also wondering why would you need those ECUs to communicate in the first place. You could simply give the basic inputs to second ECU (for example Speeduino|) and have it figure out what to do based on its own map.
I don't imagine you want to have direct injection of E85 (or... do you?) and with port injection the ultra exact sync between ECUs doesn't seem to be necessary.

[dazq]

You are correct in assuming that speeduino CANNOT run a diesel engine by itself.
It can run six injectors (petrol port style, not direct or diesel ones).
Speeduino does not support sensor data input via canbus at this time.

Speeduino does not also have the ability to adjust timing or fueling based on knock either at the moment .

[theonewithin]

Just get a devils own Water/meth injection kit or similar.

You don't need accurate fuelling in a diesel.

You need cooling so water/meth/E85.

[Won24]

So, I will be doing port injection. Ideally I wanted to have an injector for each cylinder. I realize that's slightly overkill, but I wanted a high level of control.

I'm open to the idea of running the two ECUs separately but that creates other difficulties. I suppose I could get them to half assed communicate through outputs and inputs.

Water meth injection is great for diesels, but it's not supplemental fuel. From the research I have read you can supplement about 30% e85 under full load and 70% with no load. Now, you can read that two ways. Since diesel is a fuel limited engine, that's either throw 30% more engine at the road, or have your diesel be a little more economical. The other advantage is I can drive up to a pump and get e85 for cheap, I can't do that with methanol.

Since I'm trying to run e85, naturally ethanol content will vary... Which means I'll need a map based on ethanol content along with a flex fuel sensor. The research I've read indicates over supplementation leads to knock.

The other interesting thing is e85 supplementation leads to higher flame front speeds which means theoretically it could have a higher rpm.

[jonbill]

are you doing hybrid diesel/spark ignition, or diesel for both fuels?

[Won24]

Diesel is the ignition source. In the most rudementary sense I am just spraying fuel into the intake.