Base timing. Really ?

General terms.
let’s say 20 degree initial
I am not sure about how much the vac Adv is right now
Mechanical should be restricted so the initial + mechanical + vac = total around say 34 degrees ?

Another question is the vacuum ( which I won’t have much of ) comes and goes due to load and throttle position. Needs to be fully in this equation ?
Thanks :poke: