OM642 Higher Fuel Rail Pressure Sensor

SaundersW203

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Hello Everyone

I have a v6 OM642 (diesel). I'm at the limit of my fuel injection system, to inject more diesel efficiently, I need to increase my rail pressure. The current fuel rail pressure sensor is 1800Bar, does anyone know of a "bolt on" sensor that is around 2200Bar I can use?

Thanks,
Adam
 

mersum1es

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whatta heck you are tweaking? Are you on limit on injector opening time already? Get bigger injectors, C30 AMG's are good place to start...
 
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SaundersW203

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I'm not sure c30 AMG injectors would be any better. The OM642 has some pretty good injectors.
I'm injecting 115-120mm3 of fuel. I made an excel spread sheet so I can check my EOI and it's at 3-4°ATDC. I have already added a couple of degrees to the SOI. I'm reluctant to take it further.
I'm running quite lean with regard to lambda (1.3).

Next step is more fuel pressure and water injection because EGT's are quite warm. haha
 

mersum1es

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Rising pressure above normal limits its not normal procedure when gaining power. Icreased injection time can be done until it disturbs mixing before cimbustion. AMG injector do have pretty good addition to flow capacity, what hp levels you are targeting? Fooling pressure is stupid way to do things, if you are heading 'decent' leveles <500 hp I belive you can do it without going excessive pressures.

Basics is: sliglty risen fuel pressue, risen injection times, much more better intercooler, wider nozzles/injector bodies, better performace turbo.

I am not expert of tuning, but done some search before got my C219 remapped, 280HP level
 
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SaundersW203

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400bhp would be enough. I don't think the pistons/ rods would take much more than that!

Normally too much SOI leads to cracked pistons, bent rods or the head lifting off the block.

Pressure will almost always increase no matter what you do, I have seen it myself. But different tuning methods and hardware limits dictate how much of an increase you get.
I have seen 3L diesel engines make 360bhp 750Nm with just 90mg of fuel. That's quite impressive....cylinder pressures were high though. Or you could use 105mg of fuel and get the same torque and power just with less cylinder pressure and less efficiency. If the engine can take it, why not use less fuel and produce less heat.

In a diesel, more fuel = more heat. Everything is a balancing act, SOI, Duration, IQ, EGT's etc.
I work in engine development, although I only have little diesel experience I've got a pretty good idea what's going on.
I do all my own calibration work (ECU tuning) along with relevant hardware mods/ changes. I'm currently running around 350bhp...
 

Supernoodle

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If you increase fuel injection rates and pressure you'll probably find that the pump won't be able to supply enough or at least rail pressure control will suffer.
Have you managed to get an a2l file for the SW then?
 

mersum1es

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smoke is limitig fuel feed in these... like said going over 400hp you can't do pressure/timing alone. Read tuning threads and you will find lotsa info... part list I referred (cooler, turbo, injectors) is close your next actions.
 
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SaundersW203

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If you increase fuel injection rates and pressure you'll probably find that the pump won't be able to supply enough or at least rail pressure control will suffer.
Have you managed to get an a2l file for the SW then?
No a2l for this exact software but lots of hours comparing something very similar and then making a map pack....
 
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SaundersW203

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smoke is limitig fuel feed in these... like said going over 400hp you can't do pressure/timing alone. Read tuning threads and you will find lotsa info... part list I referred (cooler, turbo, injectors) is close your next actions.
Stock turbo runs out of puff at 280bhp. I've got a 2365 hybrid.
Already got a larger cooler and associated pipework.
Injectors are more than capable with additional fuel pressure.
 

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