Thread: 51 MG restoration.

Your eyes do not deceive Jerry. It does, or did have both mechanical and vacuum advance for different load conditions.
I have, on Toms recommendation, disabled the mechanical flyweight advance and will leave the vac advance enabled still with the MSD system.
Will pull the condenser off tonight as I missed that in earlier discussions but with the absence of voltage anymore, it’s just not needed.
Cheers..

Well at least it's pre 70s black spaghetti under the hood with all the vacuum emissions control insanity.

Gapped my points and removed the condenser so good to go there now!

And I’ve traced out the old rear wood rail onto one of my last pieces of oak to make anew. Figure after looking at it that it was home made, whereas the two small side pieces were original and there is a difference in height between them.

Even if the height was good, considering the convertible top connects to this I’d like new solid wood, sealed in the marine grade epoxy to also stand the test of time, like the rest of the car.
The new top will wait till the car is running again so I can go have some fun, and properly clean out the garage before I get into it.
May be able to actually have it running before to long now.
Cheers!

I will repeat my dribble once again.
MSD like this will produce a hot spark for 20 degrees of rotation, give or take considering resistance, etc.
This means advance is out of the window for this period as spark will be present and not need to be advanced.

I would recommend disabling the vacuum advance as well. Checking total timing and desired will determine what advance could be tuned. FME it ain't gonna be ported/ manifold vacuum. Stiff springs on the weights wil get more advance as the mill is screaming.

Lock it all out and determine base timing (where it seems to run best).
Check total advance and see specs. (not that that matters!)
You might be surprised. Starts good. Rattles on accel, retard timing until rattle is gone. Binds on start? Too much advance. Heavier springs/lockout.
Hard to start? Retard timing til starts easily. No rattle up top? Window too narrow. Lighter springs.
You can change just 1 spring to get incremental.
Tuning.

In the UK there is a store called Halfords, it sells car tools and parts as well as other things.

I bought a kit there once, it was a sort of glass spark plug affair, that a person replaced a spark plug with (just for the test).

The idea was that a person could see the colour of the bang.

I can't remember why it said I needed to see it now but regardeless, I used to do my timing with a strobe lamp.

Nice explanation, Tom. Thanks for that. It makes full sense to me. I don't know the engine Mike is working with but I do know mechanical advance seems more accurate if needed. Here is to hoping no advancement is needed at all being it has such a wide range!

Ahh the ole colour tune system Steve.
Those lil glass windows were for setting optimal fuel mixture not spark.
Could dial in your mixture lean or rich based on combustion glow.
Still used in motorcycle worlds and old car racing I’d imagine.
And thanks for the write up Tom. Lack of any advance just seems wrong to me. I get what you are saying though so am eager to get her rolling again to get her dialed in.