10 replies to this topic

[cristiano1968]

Hi
Any one know how to calculate ignition timing using the number on the distributor plate.
for dynamic timing etc .
Got a 59d lucas distributor 998cc engine

[Spider]

There will also be a 5 digit no. stamped on the body, it may also have some letters with it and usually the no. will start with a 4xxx, eg

 

 

41537

 

that is the number we need.

[jaydee]

http://members.home....distributor.htm

 

This will help you further

 

 

NOTE:

You're likely to use different advance (+/- 2 degs) with modern fuel.

Edited by jaydee, 28 September 2015 - 02:19 PM.

[cristiano1968]

Thanks for the link.
Just my luck
No etting for my 1989 mini😨

[carbon]

Cristiano,

 

If you take the points baseplate off the distributor (2 screws) you can see the advance mechanism. There should be a number stamped on this, probably between 7 and 12. This number is the original amount of total mechanical advance, as distributor degrees. To work out degrees total advance at the crank multiply this number x 2.

 

So for a dizzy with 10 deg mech advance stamped on advance mech will be total 20 degrees at the crank. To work out the total max ignition advance add together the static advance to the total mech advance. If you timed points to open at 8 degrees static this would be total max advance of 28 degrees (without vacuum advance).

[cristiano1968]

Thanks carbon.
Forgive me as I'm italian.my English is so so.
My distributor under base plate has 10 on it.
So my advance setting would be 10 degrees at 1500rmp ?
So my total mechanical advance is 10 +10=20
So 10+20= 30 total max ignition advance ?
So use my timing light with dial at 30 degrees and set up the line at top dead centre the first pointer?
At what rmp speed ?
Or have I got it wrong?

[carbon]

Christiano, if you have 10 stamped on the advance mechanism this will give 20 degrees maximum mechanical advance. Without knowing the advance curve for this distributor it is not possible to say at what rpm you will get maximum mechanical advance.

 

Also the static advance timing will depend on the engine, for this you need to refer to workshop manual. And please bear in mind that for many Minis (before late 1980's in the UK) this timing was for leaded petrol at 98 octane.

 

If you are using 95 octane unleaded the timing will need to be retarded when compared to setting for 98 octane fuel.

[Spider]

http://members.home....distributor.htm

 

This will help you further

 

 

NOTE:

You're likely to use different advance (+/- 2 degs) with modern fuel.

 

I've had a look at that list once before. I'm not sure where it came from but doesn't appear to be a Lucas List, it's not complete, however there are also a number of errors in it.

[cristiano1968]

Ok Thanks for the advice.
My mini manual that came with car has
Written
10 degrees -2 at 1500rmp vacum disconnected.
I do have a mini spares stage one kit on my car by the way.

[carbon]

Cristiano, would suggest starting with about 10 degrees static advance, measured and set using flywheel markings. Then try this on the road and see how it goes.

[cristiano1968]

Hi carbon.
Mines a 1989 mini
No flywheel markings.
Was of work today.
Set it at ten more or less it wobbles a bit .
Then I tested it on road and tweaked it a bit.
Then I tuned my su carb.
I used a gunson gas meter got it to about 4 Co at about 800rmp idle
Runs quite well.☺☺