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Megasquirt on a Diesel?

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Would it be possible to use the megasquirt system on a diesel?

To covert a 200/300 TDI to a common rail diesel (using some commonrail parts from for example a td5)

And injectors from a ???

Maybe a stupid question.. just curious..

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Not that stupid - just very tricky, diesel fuelling is more complicated than petrol fuelling, last I heard they were working on it though. Try www.msefi.com, you may need to register to see all the forums as they have a "high tech" area for development work.

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Would it be possible to use the megasquirt system on a diesel?

To covert a 200/300 TDI to a common rail diesel (using some commonrail parts from for example a td5)

And injectors from a ???

Maybe a stupid question.. just curious..

In theory, yes. I looked at the possibility of running a TD5 using Megasquirt and the only real issue I came up against was the voltages needed by the injectors as I've been told (although never had it confirmed) that they run off 48v. Having said that I never got past the "in theory" stage so no idea if it would have worked or not :) The TD5 injects above the valve so injection timing isn't an issue. I was told that each injector has to be calibrated and that the TD5 ECU gives each injector a different pulse length based on the calibration, not sure how much of that is really necessary though.

Can't see it being that complicated though, after all if they can cope with the problems of using a mechanical pump/injection system an electronic version should be a doddle...

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The TD5 injects above the valve so injection timing isn't an issue. I was told that each injector has to be calibrated and that the TD5 ECU gives each injector a different pulse length based on the calibration, not sure how much of that is really necessary though.

Yep.

TD5 uses a bespoke injection system - Think of the injector as a combined valve and injector pump. Because individual injectors release slightly differing amounts of fuel for a given injection cycle, each is calibrated so that the ECU "knows" how much fuel will be released by each injector for a given pulse length. To set it up properly, the ECU needs to know the calibration of each injector - which is done via Testbook or similar.

It was a unique system developed by Land Rover. I heard it likened to driving a chariot with 5 horses, each one with it's own set of reins... ;)

Matt

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It's entirely possible - usually the fact that more than one person has asked for it means it'll appear at some point, the MS3 will likely have the necessary features to do it even if the software isn't there from day 1. Not that it isn't possible with current hardware, it just means some tinkering with hardware & software.

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I had the impression that the Td5 injector was driven from the cam but not that it has anything to do with the valves.

I do not understand the term 'The TD5 injects above the valve so injection timing isn't an issue'. Are you suggesting that Td5 induction is more like a petrol engine in that the fuel enters the cylinder with the charge air? I do not know but that seems unlikely.

Chris

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Very interested in this too. But is it not simpler to use edc bits and bobs from a late 300tdi?

Can any one explain the difference/benefits between the 300tdi where all the solenoid control seems to be in the pump, and the later td5, where is its at the injectors? Or is it not this simple?

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Bear in mind it's a couple of years since I looked at this so the details are a bit vague now... it was one of those off the wall conversations I was having with a mate who was in the process of rebuilding a TD5 to fit in his 90 and he asked if MS was an option on it. My first reaction was that it couldn't be done because you needed sequential injection and, being 5 cylinders, this wasn't going to be easy on MS. After looking at the way the injectors were arranged in the disassembled engine that was ruled out as a problem.

I'm pretty sure now that we decided that the TD5 uses a "fuel shot" system like a petrol EFi does, stored in a chamber behind the intake valve and for that reason injection timing wasn't an issue. The only thing standing in the way of bank injection was the aforementioned unique injector opening times although I suspected that was more of something that was nice to have "because they could" rather than something necessary to have.

How/if you would be able to reproduce this on a 200/300 TDi is a different question altogether of course !

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Very interested in this too. But is it not simpler to use edc bits and bobs from a late 300tdi?

The short answer is yes - an abacus is simpler than a laptop but most people use a laptop these days. :P

MS has always been about keeping things relatively simple, hence why they're shied away from sequential injection in the past - petrol engines don't really need it. I don't know how far away MS3 is and what it will and won't do. Last time I looked there was talk of a sequencer board to allow sequential injection from existing MS units.

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The short answer is yes - an abacus is simpler than a laptop but most people use a laptop these days. :P

Sorry i was only suggesting the using all the components from edc that are known to work... some of the time, except the ecu.

As far as i can tell that would give you:

Mass air flow

Fuel temp ( although thats part of the fuel pump)

crank position sensor ( could be an issue as theres no bolt on flywheel, as edc only came on autos)

inlet temperature sensor at manifold

boost pressure( in the injection pump)

boost solenoid

injector that detects tdc (i think)

Don't think there is much else...

Any way as the original post, looking at td5 injectors they will not fit a 200/300tdi head. Although Td4 ones look like they might.

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Bart, first TD5 is not common-rail, second Td5 injectors are driven by the camshaft, so no way you are going to be able to use these on a tdi....

If it could be done, I think it would be of no use. The original TD5 ecu has all the options you will need for tuning.

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I see the primary application of a MS type system with current fully electronic controlled diesel engines such as BMW 3.0; Td5; TdCi; TDV6/Jag; TDV8 etc where fitment to an older Defender / RRC could be problematic due to the ECU and what it expects to communicate with (the Td5 seems to be reasonably well understood as evidenced by fitments to older vehicles reported on this forum). Also, diesel ECU's are 'closed architecture' to those of us tinkering in garages and lock ups.

Another plus would be the ability to talk to/control other functions i.e. the transmission controller for a more modern or stronger gearbox; a VGT in place of a conventional wastegate turbo; etc.

As I understand it, the issue with MS controlling a diesel is not just about sequencing - that is already handled for the sparks on a PI system. DI requires both timing for the start of injection (relative to TDC) and a duration (to determine the quantity of fuel injected) whereas electronic ignition requires timing and will run with a fixed dwell angle. Injection timing within the cycle isn't too critical on a PI system, hence bank firing of injectors is acceptable.

Consider a 4 stroke diesel running at 5000rpm. The combustion cycle is of ~6mS duration. 8 bit resolution for control of the duration of injection would require a dynamic timing accuracy of ~20uS (and possibly considerably less). To achieve this might require a different design controller as it would be asking a lot of MS to do both timing and duration calcs for DI.

BTW: It may be of academic interest to try to take a 300Tdi to a higher spec, but there are other more advanced engines on the market to play with. A halfway house might be to use a Bosch VR pump instead of the VE and use a simple controller :ph34r:

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Just to add 300tdi injectors are a smaller diameter to 200tdi's so td4's would probably only fit the 300tdi.

TD4

td4.jpg

300tdi

300tdi.jpg

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To me why would you try and megasquirt a TD5 - you can put the wiring loom in your 90 anyway???

However, I agree with Dave11A, the use would be for the more modern engines such as the TDV8 etc. this would make fitting these far more practical. However the TD6/BMW 3.0 versions can be made to work quite easily. The pre 2002 versions just need the security units fixing. After that you need to spend more. Rally raid UK can 'fix' the latest 285HP version. But they want ~£1000 for the wiring loom and ECU. The same could be done for the TDV8 if there was enough interest in it, but costs would be high. Mega squirt would be a far more cost effective way forward. How ever I think that it would need to include the following funtions over and above the those mentioned by Meccano.

Abililty to:

Control boost pressure using a solenoid valve in conjuction with a pressure sensor (preferably on two turbos, i.e. twin sequential turbo's on the latest BMW 3.0).

Control inlet valve swirl flaps on 4 valve per cylinder engines

Cam position sensor

control pressure valves on common rail engines

The big one though is the injectors. Diesel injection timing and flow rates are far more complicated than a petrol engine (to my knowledge). If you want a quiet smooth running engine with good exhaust emissions you need to be able to:

Provide pre injection before TDC

Control timing, flow and duration during injection event.

Post burn injection to give better emissions.

A good book on this is 'Diesel engine management' by Bosch. A 500 page book!! and it only covers the injection pump, turbos, emissions, injectors. They also do one on Gasoline engine management which if it as detailed as the diesel version would be very good reading for the petrol heads.

Adrian

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so you could use this ms3 to run the tdv8 as a stand alone rather than try to seperate the engine ecu from the bcm or try to persuade landrover/jaguar to sell you a stand alone ecu? now that would be interesting........

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Adrian,

MS has most of your list covered through existing functions, and can read almost any existing form of crank/cam/flywheel sensor and MAP/MAF sensor as standard. The main issues are the resolution of the standard MS-I unit (upgrading to MS-II gives 1uSec resolution which may or may not be enough) and the pre-injection / injection / post-injection sequence which would need to be programmed, assuming the existing MS has enough spare capacity to hold the additional programming & maps for all this as I can't imagine they're just a fixed function of the main ignition event.

The benefits of the system are similar to those you get on petrol engines - the ECU is much cheaper than commercially available units, either OE or aftermarket ones, and everything is open source and well documented & supported. It also develops much more quickly as you have tens of thousands of petrolheads out there playing with it, tuning thousands of different vehicles with it, and working on new features.

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Post burn injection to give better emissions.

So, I burn extra fuel to get the emissions down? Interesting. Assuming that I was not bothered about exhaust emissions (which, of course, I am!) could I get better fuel economy with the same power by removing this 'post burn injection' from the injection map?

Chris

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First thing you'd do would be to throw away your catalysts and particulate filters. A number of the current technologies use exhaust heat to enable exhaust catalysts to trade off the oxides of nitrogen (NOx) with carbon monoxide (CO). For example, the exhaust gas recirculation reduces NOx (because it replaces oxygen in the cylinder and interestingly has a high specific heat capacity so the charge doesn't reach the very high temperatures required to form NOx) but CO goes up - but CO can be tackled in a catalytic converter. Catalysts generally need tobe kept hot to work well, hence post-injection allows fuel to burn down the exhaust. Some heavy duty vehicles even have a seventh injector in the exhaust upstream of the cat!

Unfortunately both of these increase the fuel consumption (and so the CO2 emissions) - until maybe three years ago this was less of an issue but the argument is now becoming "local emissions or global emissions" and arguing against the tiny reductions in harmful tailpipe emissions by large increases in CO2 emissions is rather pushing against an open door among engineers.

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Hoi Newbie uit Schoonebeek

hoe staat het met jouw project om een 300tdi om te bouwen met een megasquirt

ik probeer mijn TD5 met een Arduino te laten draaien, maar dat gaat maar heel langzaam vooruit

groet Chris

Would it be possible to use the megasquirt system on a diesel?

To covert a 200/300 TDI to a common rail diesel (using some commonrail parts from for example a td5)

And injectors from a ???

Maybe a stupid question.. just curious..

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Welcome to the forum Chris,

If you can use a translator such as google, You will get far more help :)

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So, I burn extra fuel to get the emissions down? Interesting. Assuming that I was not bothered about exhaust emissions (which, of course, I am!) could I get better fuel economy with the same power by removing this 'post burn injection' from the injection map?

Chris

Wooooh this is an exiting tread :blink: Why not just wind the elastic band up a little more :lol:

But seriously what is everone trying to achieve????

All the guys we race against have tuned tweaked etc TD5s or TDIs & to be honest on a average say 70km race day they burn around 1/3 less fuel than the Big V8s with a lot less power !

How much does it cost to modify these diesels to get 1/2 the power we get from the V8s ??

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You're not wrong Pete, but the advantages aren't just MPG related. Dropping the factory EMS means diagnostics becomes easier and the whole system gets a bit simpler and hopefully more robust. There's also "just because you can" :P

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