Hello all,
This distributor was fitted to a US specs S2, with an ignition amplifier and a vacuum retard.
I cannot find a description of it in the manuals I have.
No breaker points, no condenser. Is it magnetic? Is it any good?
I plan on using it on a European specs engine with a vacuum advance.
Any thoughts?
Thank you.
It is magnetic, like in the S3, but looks like vacuum retard which you already know. If you want to use it you need the ignition amplifier, which you know too. The star wheel is read by the sensor and switches the amp.
It is all described in the Haynes Manual, but Haynes use a lot of factory material so it will be there too. US only. Everywhere else only S3 had EFI and electronic distributors
Thank you David. Is it a stock Jaguar setup or aftermarket?
The sensor board and trigger wheel are Jaguar (Lucas), and look exactly like those I have, but my S2 knowledge, especially the FI cars, is nonexistent so you will have to check the literature. I bet it’s stock.
Thanks. Just to be clear, the engine is with 2 HIF carbs, not Fuel Injected.
That’s a CEI ignition. On the V12, that was introduced many years after EFI. I know little of the 6 cyls, but find it difficult to believe a car came with CEI and carbs.
Actually, now that I think of it, I believe the S2 US spec was a version of OPUS.
Will check.
Edit: My factory Manual is 1972 and has nothing. My Haynes nothing (I didn’t check the S3 section) so it must have been a photo essay/article somewhere. Never had a late US-spec Series 2 6cyl, only a late S2 12 cyl, so have no personal experience.
Then this one has been upgraded to a CEI. That’s a good upgrade.
Indeed, US cars should have the OPUS system even before introduction of FI: it is a Lucas 45DE6 or Lucas 43DE6 for California. Only the 45DE6 have vacuum advance capsules. “An additional component which is essential for the correct functioning of the Opus system is a drive resistor, wired in conjunction with the transistor in the amplifier. It is located on the coil mounting plate stud adjacent to the distributor and shares its power supply with the ballast resistor (for the coil) to which it is connected by a white lead.” (SII ROM, 86.35.00)
Good luck
Jochen
75 XJ6L 4.2 auto (UK spec)
Ok, so a Lucas Constant Energy Ignition system. I will look for info.
Thanks.
Interesting articles:
FWIW…
Jaguar offered a retro-fit kit to convert OPUS to LUCAS for the Series II 6 cylinder cars. There’s a TSB on it.
Cheers
DD
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There should be two wires from the dist, Eric, going to an amplifier - or at least a connection for them. As David says; you need to source an amplifier - without that an electronic dist is useless. And as Peter implies; this seems to be a S3 dist for US market - which would use the AB14 amplifier/igniter…
You cannot use a vacuum ‘retard’ dist in the ‘European’ vacuum advance set-up. However, the engines for all markets are the same - it’s only the ‘externals’ that differ. Ie, if you use this dist; it must be connected to ‘ported’ vacuum using ported vacuum centrifugal advance specs - manifold vacuum will not work…
Frank
xj6 85 Sov Europe (UK/NZ)
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I‘ve been wrong there and learned that the S2 has apparently had several ignition changes. I don’t have any catalogues but let’s say it could be that it is S2 and either way it fits, and is superior to points. It’s just the retard that makes me not like it (not saying it’s bad), but that belongs in the other thread.
Update.
So, this is a Lucas Constant Energy Ignition (CEI) distributor, model 45DM6, fitted in US specs S2 XJ6 (and may be S3). It uses a magnetic pick up, no breaker points, no condenser. It uses a vacuum retard valve that allows better combustion at some RPMs to satisfy emission regulations are the time (many other cars used the same set up). It is mated to an Ignition Amplifier unit (that contains a simple GM module). This set up can allow to use a low resistance coil, under 1 Ohm (although, need to confirm this one).
As stated many times before, this was originally fitted to my full US specs (Stromberg, EGR etc) XJC when I bought it, worked perfectly.
The car now has a (fully rebuilt) Euro specs engine (with 2 HIF carbs, no EGR) that i will crank for the first time today if all goes well.
On partial dismantling and inspection, the CEI proved in excellent condition. I fitted it with an ADVANCE vacuum valve.
I will use this CEI distributor, with its original amplifier module and coil, with the advance vacuum valve connected to the “ported” spigot on the rear carb.
Let’s see how this goes 
Don’t forget to film it, hope all goes well
Strobe time it to full advance - mid thirties by about 3000 with vac plugged. The weights will almost certainly give a different advance to non-emissions distributors, so the full advance timing (the important figure) will be wrong if you just time static or idle. If you time to full advance the idle running can be tweaked by carb adjustment.
The baseplate slot may need changing/adjusting when asked to rotate the opposite direction under advance vacuum.
Distributor in my place.
My objective today was to crank the engine to confirm that the starter motor works and oil gets to the camshafts.
All good except, it seems to me that the starter is not cranking the engine fast enough… Thoughts?
I think, good. Fast enough. I‘m uploading what my s3 sounded like with the plugs out.
Run-in engine and battery charged fully, so yours can be a bit slower.
Yes, plenty fast enough and likely only achievable with plugs out?
