P38A Running a 2.5 engine "stand alone"

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300bhp/ton

300bhp/ton

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Further to my EAS question.

What is the easiest way to run the BMW 2.5 M51 diesel engine, if you wanted to ditch most of the p38's wiring harness.

Can the engine ECU be run without the rest of the control systems?

With a V8 p38 it would be easy, use an older RV8 ECU (Disco1/RRC), Megasquirt or even chuck a carb on it.

I'm not sure how this can be done with the diesel, as I assume the engine and BECM have some communication. Could a BMW car ECU be utilised? Or is there an easier way? Not fussed about keeping the engine immobiliser. Just want to start/stop the engine, have it run correctly and still allow it to be mapped/tuned.
 
ECU is linked to the BECM which grants permission to run. So I think you would need both still.
Injector pump has a PCB which must match the vehicle. 3 different numbers associated with pump which only work with certain cars (VX Omega, BMW 3/5 series and LR)

I stand to be corrected :)
 
Hmmm. Good question.

I think the only thing it needs to run from the BECM is the grant from the security code and if you replace the chip but leave it unsecured it probably doesn't need a code at all. Someone with an EPROM reader could probably copy yours to a blank chip in no time, leaving the code blank. I've seen Megasquirt used on petrol but not diesel, although I guess it might be possible.

This guy seems to have knocked something up using an Anduino for a VP37 pumped diesel: https://hackaday.com/2012/07/10/building-a-homebrew-diesel-ecu/
 
You can buy a new ECU which will be set to "Unsecured " mode, then nothing is needed. Once set "Secured" mode, it cannot easily be changed, but search the internet, I believe someone has found a way. It could also be done with a Rasberry Pi or Arduino to provide the code.
 
Datatek said:
You can buy a new ECU which will be set to "Unsecured " mode, then nothing is needed. Once set "Secured" mode, it cannot easily be changed, but search the internet, I believe someone has found a way. It could also be done with a Rasberry Pi or Arduino to provide the code.
Click to expand...
Any idea where I could get an Unsecured ECU from? Thanks.
 
300bhp/ton said:
Don't suppose there is any handy info on doing this anywhere? I've not been able to find much.
Click to expand...

@Dopey 's mate, Max, down at Heathrow can copy the chip for you and leave it unsecured. Guess he'd charge maybe £200 notes but might be worth a call if he's still around and not buggered off back to Poland. Or I bet @martyuk could do it. Not sure what he'd charge but the chips cost about a fiver.
 
To fit a mechanical VE it would need fitting static timing at 1.54 mm before TDC and a pressure pipe fitting from the turbo. It is also easy to trim fuel for a bit more power, but has to be done carefully. Feeding rev counter maybe a problem. But the electrical lads may know more about that.
 
Good point. I bloody don't... And I imagine when all the electric cars have done a good few years on the road their second hand value will be peanuts due to "just needs new batteries":eek::(
 
wammers said:
To fit a mechanical VE it would need fitting static timing at 1.54 mm before TDC and a pressure pipe fitting from the turbo. It is also easy to trim fuel for a bit more power, but has to be done carefully. Feeding rev counter maybe a problem. But the electrical lads may know more about that.
Click to expand...
A rev counter can be run off the alternator as is done on many diesel vehicles. Needs either a mod to a standard alternator, or alternators are available with an output for a rev counter. May not suit the P38 rev counter though.
 
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