Manifold Vacuum Advance what am I not getting?

Turk,
I know your engine would idle better with more timing because I have doing this for so long.

It is called experience.
Pay for my plane ticket & I will come & dial in the idle timing..... the proper way.
One engine I tuned, close in specs to your engine: 11.3:1 CR, alum heads, headers, T2, Holley 950, 254/262 @ 050 HR cam, 108 LSA. It idled best with 48* which was done by giving it 18* init + 30* MVA.
You keep going on with your NONSENSE about people picking the wrong cam/pistons. Maybe some do, but they decide to live with the decision [ & save $$$$ ] & tune the engine accordingly.
How many people reading this are building engines with 12.3:1 CR, 255 * @ 050 cam, tunnel ram with dual 800 carbs???????? Only one I know is YOU, especially if it is to be street driven.

The facts are the facts. Factories & racers alike use[d] MVA. And they didn't have 12:1 CR.....
Below is another one, four cyl engines...
They cannot all be wrong be wrong.

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