Distributor Vacuum Advance Adjustment

[Boaf 32]

All,

I have a question on Vacuum advance adjustment. I have a distributor in my 72 LC (Mnf. in 10/71). Not sure if it is the correct one. Here is a picture from another post. Is the dial located on the opposite side of the vacuum hose the adjustment for the advance?? What should that be set at?

Thanks, trying to go back to factory settings (even though the carb is a weber).

Boa

 

[73FJ40]

That dial is known as the "octane selector". It's supposed to be initially set at 'zero' and then only adjusted 'retard' or 'advance' (R and A on the distributor housing) when dealing with low octane fuel, and the ability to return to 'zero' when the fuel improves.

 

[Boaf 32]

Well that's interesting. Old fuel sucked back then... So is there an adjustment for the vacuum advance? In an old mustang I had, you used an Allen wrench in the vacuum connector itself, dialed left or right to get the correct vacuum.

Thanks for the snapshots.

Boaf

 

[73FJ40]

Nothing in the factory service manual about an adjustable vacuum advance.

Note that the octane selector only moves the points mounting plate relative to the vacuum advance connection. It's the equivalent of rotating the distributor housing to advance or retard the timing, but has the distinct advantage of returning the timing to standard without the need for a timing light.

 

[Boaf 32]

You answered my next question which was, "So I can advance and retard timing with that Octane Selector". Now that's sweet. Thanks!

Pictures coming soon of the before and after painting!

Boaf