Cruise Seems Lean

71GSSDemon said
If initial timing with vacuum advance disconnected, is set at 18-20 (already well above factory settings) this additional timing is there. Then if connecting to ported vacuum, it is as set. If connected to manifold vacuum, it will be considerably higher but only until the throttle is opened - same as ported vacuum as it is equal to manifold vacuum once the throttle is open.

This is correct

71GSSDemon said
So, with a more aggressive initial timing and the mechanical timing limited due to this, are we talking the same thing to some degree (pun intended)?

To some degree yes if you look at it in the way you just did.
In general no, because its fixated on a belief that extremely early timing and lean burns produce power.

@yellowrose
Sorry, My post was referencing
Sorry your post #101 on vac adv is totally incorrect. Set any Chrysler 6 or V8 engine to the factory initial 6-12* timing. With the engine idling, turn the dist slowly to advance the timing. Idle rpm will increase [ more hp ] & vacuum will increase [ increased efficiency ].

@71GSSDemon mentioned he had read Shrinker's posts, in particular the paragraph from post #10. Bewy obviously chose not to, or did but choses to believe the current magazine writers are more knowledgable. The two big points from Shrinker in those two paragraphs is that early timing goes with lean burns and there has to be enough later burn to push the exhaust out. Elsewhere he explains why lean burns are foolish at idle, but the bottom line is they don't make power. Maybe I can dig that out later and post it up. Tests in neutral do not indictate power.

@71GSSDemon following upo on 512stroker's question. Remind us. Was the vacuum advance connected during this last drive? and if so where?