Club 80-90 Forums

Hi All,

I plan to take the 2.1 MV out of my syncro for a rebuild, and so that I can take my time with it, I want to install another engine in the meantime.

I have a spare 1.9 DG that I acquired.  So the question is, can I install the DG as-is and run it on the MV's Digifant system?  The Digifant has lambda control so hopefully it will automatically fuel as required for the smaller displacement?  Has anyone done this before and what were the results?

The alternative would presumably be to rebuild the 1.9 DG as a 2.1.  I understand that this should be possible with a bit of clearance work on the crankcase?  I plan to strip down and do a light rebuild on the DG before it goes into the vehicle (as practice for the MV rebuild), so I could do the upgrade to 2.1 spec at that point.  But I would rather not get involved in purchasing new crank, pistons, etc. for a engine that is only a temporary stop-gap - easier if I can keep it as a stock 1.9.

Thanks!
 

I don't know from having done it, but I reckon the Digifant will cope just fine on the DG, because it is a bit more adaptive than DigiJet with the feedback from the Lambda and the ability of the ECU to control both fuelling and timing; you might just have to play around with the initial timing a little bit, but we do that running LPG and generally I can find a compromise setting that works for both LPG and 95 RON petrol, 8-9 degrees worked well for me

I've run a DG on Digijet very successfully, but not Digifant. However, I agree with Aidan that it should deal with it very well, for the reasons given.

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Im doing a similar exchange in late summer. Putting in a temporary early DG while giving a top end refresh on the DJ. Have been reassured by many on here it will be fine. In fact, l believe it is designated as a SP. 1.9 fuel injected...is that right?

Good luck with the rebuild

Not SP, that's on a carb. It's either a GW or DH.
It's identical to a DG, but puts out a (claimed) 90bhp on digijet.

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ajsimmo wrote: ↑28 Mar 2021, 20:26 Not SP, that's on a carb. It's either a GW or DH.
It's identical to a DG, but puts out a (claimed) 90bhp on digijet.

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Ah yes! GW. That's the one. I easily confuse myself nowadays. SP is Zoona's Swiss speccd engine.

Thanks all, sounds like the DG+Digifant should work fine.

It will be a few months yet, but I will post back here when I have the DG installed, with some info on how well it runs with Digifant.  It's only a temporary solution, so as long as it's reasonably driveable then that's good enough.

Next question - am I right in saying that I will need to tap an extra oil pressure port in the DG case for the MV's sensors?  Or I could presumably run a T-piece instead.  Are there any other mods that I will need to make to the DG for it to be accommodated into an MV/Digifant setup?

Cheers.

Is it a early DG ? If so it won’t have the second oil pressure port , but you can defeat the buzzer with the wiring .
late DGs have the second port and will be the same as your MV 

oil pressure isn't part of engine management, it's just to talk to the dash dynamic oil pressure system, as Steve says can be defeated if the block hasn't got the second tapping to the oilway.
If you are fitting the full later plumbing you'll have to change the oil filter fitting to the long one to take the oil warmer cooler and use the 2.1 thermostat housing with the temp2 sensor

Mocki wrote: ↑29 Mar 2021, 16:49 Is it a early DG ? If so it won’t have the second oil pressure port , but you can defeat the buzzer with the wiring .
late DGs have the second port and will be the same as your MV 

Good question!  As I understand it, the primary oil pressure port that all engine types have, is the one under the pushrod tubes, and the second one that is only on the MV and later DG engines is the one between the alternator and water pump pulleys?

If that is correct, then can someone confirm that blanking plug shown in the following photo, above the engine mounting stud, is the one?  If so, then it looks like it's a later DG.



As an aside, the cast numbers on the casings are 025 101 101 B and 025 101 102 B.  There is a post from Rocky Jennings that I saw on The Samba that says that the "B" suffix denotes a 2.1 engine.  But since this is definitely a 1.9/DG engine, I guess that he meant to say that the B denotes "a 2.1 or a later 1.9"?
 

Yep that’s where the second sender should be . 
all later wbx have this port , early don’t .