This 29D4 is fitted to a 1968 998cc minimatic, engine no 99H 119 H599. Can anyone help with any points on the advance curve for this unit and the specifications for the associated vacuum advance module.

Does it have a serial number stamped on it? (There are two different numbers listed)

The service numbers stamped on it are 62941072A and AYG2173 11 67

Thats a bugger, the numbers I have for the two different types are 62941052A and AYA0200.
I will keep looking.

Sorry but I can't find your numbers in my books (I do not have everything!) They are not Morris 1100 number either.
I will give you the figures that I have for the auto dizzys.

AYA2000
Centrifugal Advance
Dist rpm Dist advance
2000 11°-13°
1600 11°-13°
1150 8½°-10½°
700 6°-8°
570 3°-5°
440 0°-2°
325 No advance
Vaccum Advance
3hg 10hg 7°

62941052A
Centrifugal Advance
Dist rpm Dist advance
2800 13°-15°
2500 13°-15°
1400 9°-11°
850 7°-9°
600 3°-5°
400 0°-2°
200 No advance
Vacuum advance
7hg 13hg 8°

One of my books lists a 62941069A, that's what was fitted in my 1970 MiniMatic 998.

Figures are in distributor RPM and degrees.

RPM
2000 11-13*
1600 11-13*
1150 8.5-10.5*
700 6-8*
570 3-5*
440 0-2*
325 No advance

Vacuum- 3Hg 10Hg 7*.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Thanks guys. I'll graph these out and use the boundaries to fix a middle ground.

I have another A+ 998 engine with minimatic transmission that's waiting transplant to a moke.
There's was no dizzy on this engine when it was bought and the intention is to fit electronic ignition using the Hitachi conversion that's had lots of airplay here and elsewhere.

Can I assume that this A+ engine will use similar advance curve details for it's dizzy.

I don't have curve info for the electronic Hitachi dizzys, only max advance, so do I just match the top end advance figures as best as possible to make a choice. If that's correct, then the D4R85 at 12 deg or the D4R81 at 15deg would seem to be the best choices. Any comment?

The last couple of D4R85s I've pulled down had 15* advance plates in, not 12*.
If you reduce the advance pins' slot length of these by 2.0mm (TIG weld the end of slot, then grind back out to pin radius) you will get about 9-10* dizzy advance. (make slot length 8.7mm). As Graham Russell has done with a few now.
Stock Hitachi/Pulsar springs will give you full advance by 1750-1900 dizzy RPM approx.
Working fine in my 1360...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I found a 29D4 distributor in with all my crap the other day - I wondered what it was from.... thanks

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did I tell you that I won a trophy?

On the topic of dizzys, i am going to get my d4r83 pulsar recurved would you say that 10 degrees advance is good or should it be more or less, i beleive the stock figure is 16 degrees

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77 Leyland Clubman
1293cc, LCB extractors, pulsar dizzy (recurved), cooper s disc brakes, 40DCOE Weber

Yep 9 or 10* (at dizzy, = 18-20* at crank) is the go, but watch you have a decent starter fitted, the static advance will be 10* or so to get 30* total. More if total advance is more, like my 1360 needs.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.