Cruise Seems Lean

Question on this statement, and just a question. 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. 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)?@mattax your thoughts on this statement?
The problem being is that it is very difficult to make a blanket statement that covers all applications for timed vacuum advance vs full manifold vacuum non timed timing events for performance engines. Some engines are going to react differently depending on their construction configuration.
In your case I con not recommend adding additional advance on top of your initial timing of 20 degrees.
Cap it off and drive it, you may be surprised