DG to DJ - re-jetting the standard carb

[mfunsta]

Afternoon,

Going to take the plunge and replace my 1.9DG (1989, 4 speed, 65mph crusing speed) with a 2.1DJ unit.

To anybody who has done this, what size jets did you use when re-jetting the standard pierburg?

Going to fit a new clutch and spigot bush, any other hints?

cheers

[jamesandtheopenroad]

Kevtherev knows I think. Pretty sure he runs a 2.1 with a pierburg carb.

[kevtherev]

No rejet required.
The 2.1 is a long stroke 1.9 so it just sucks s little longer, squeezes a little more, bangs a little more and blows a little more.
Mine and others have found this to be so.

[mfunsta]

cheers gents
makes things a lot simpler

[silverbullet]

Before this one dies a death...the 2E3 is probably just about OK on a completely standard 2.1 motor but...having re-bushed the primary spindle on one to fix air leaks (caused nasty hesitation & was running very lean) and now it's on top of an SS engine (9:1 compression ulta-low-emission variant of MV) fitted with a VW Speedshop exhaust, I reckon I have found the limit of what the standard jetting will provide.

It's passable when warmed up but a pig when cold, hesitant and prone to stalling despite the choke being set up properly and if anything on the conservative side. If I want it to GO then full throttle in all gears is required (OK so it's a spartan syncro 'velle C on 4.86 diffs and 700mm dia tyres = 19 mph/1000rpm but even so...)

It needs a re-jet but there seems to be precious little info on tuning them apart from setting up to standard applications and even though they were fitted to 2.4 litre LT's, my gut feeling is that the chokes are too small at 22/24mm for the engine to really make proper power as the revs climb. Torque, yes, but no power.

Basically, it's too lean because of the exhaust so to get the best out of this set-up I am going the Weber DMTR route. I have the old one off a Axeman's 2.3 litre Volvo so the standard jets for that will get it running OK.

PS The wagon will go straight to the nearest rolling road and be re-jetted to suit the application, you can't expect them to work straight out of the box as they are only supplied with "base setting" jets fitted. Neil tells me it's £100 well spent and transformed the running of his engine, gaining mpg and drivability, which is what you pay for!

[ricicles]

I think that most people on here that are running a dj with a pierburg are using LPG . As some say the carb is just a funnel. If your using petrol then get it jetted properly as the dj is a high comp engine you could have problems if it runs lean.

[Mocki]

No need to rejet for a DJ just remember to run super unleaded
I also have a SS on a DG carb once the timing is set back to 7° both on LPG and fools gold

[kevtherev]

I think that most people on here that are running a dj with a pierburg are using LPG . As some say the carb is just a funnel. If your using petrol then get it jetted properly as the dj is a high comp engine you could have problems if it runs lean.

It will only run lean if the carb develops a leak.
the compression does not make the mixture lean.

The DJ is a long stroke DG with HC piston crowns, It would be interesting to see if any kind of re jet would make any difference.... and I doubt that it would be significant.
No lean problems here or from any of my friends.

[silverbullet]

This is starting to overlap my other 2E3 topic

I can't bring myself to run the SS on Super, 9:1 engines are fine on Regular 95 RON, no risk (or sign) of pinking at 5 degrees advance. Engine has loads of vacuum, pull the pipe off the dizzy to check the timing and it stalls, so all's well there.

Just wish I knew why it's such a b'stard when cold. Won't pull the skin off a rice pudding, coughs and splutters etc. but ok once warmed up, but that takes time. Mem'sahib will never put up with that!

Was reading a bit of 2E3 info on LT forum, same symptoms of the choke coming off far too early, suggesting that the aging clock spring is to blame...

I just don't get it. The rebuilt DG had more get up and go than this thing

[Mocki]

The SS ain't never gonna be anywhere near a DJ in the pulling stakes ! But it should out shine the DG !

[silverbullet]

Exactly! It's got stonking compressions, the correct LT+ plugs to go with the green label coil for a nice fat spark, but there's still something not right. I might just lift the inlet manifold again and pop fresh gaskets under it, in case they're at fault for some reason.
Nothing else left to change...

[Mocki]

Take it you have tried the old WD40 trick ?

[silverbullet]

WD 40 inconclusive at best, mostly just made a wet mess. I've checked the thermo thingy on the airbox (unless it's got some weird fault) and the hot/cold vac unit behind the rear light, brakes are really good so it's not a servo leak. Running out of ideas q.f. Maybe a set of NEW plug leads first, just in case I've got two duff sets?
Unless the secondary choke spindle is more worn than I realized...I'll lift the manifold and carb one last time then it's Weber time.
WebCon are only a few miles away, so worth a call to get basic jettings for a 2.1 and see if they can supply an adaptor kit on it's own.

[itchyfeet]

Was reading a bit of 2E3 info on LT forum, same symptoms of the choke coming off far too early, suggesting that the aging clock spring is to blame...

not sure if it's in the wiki but there is a screw which allows major adjustment of the 'clock spring' it's round the back and may be seized, once slackened the spring can be adjusted with the small hex screw on the end of the choke mech.

[silverbullet]

Collected the Weber today, let's see how it pans out...

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