Power Valve Selection

And all I am trying to point out is that there is a sequence involved in carb tuning [ no matter what the brand is ] once the engine is modified.
A sequence.

Just like when you fit a new tyre. You put air in it before you balance it.....

Likewise with the carb: the starting point is getting the correct amount of timing at idle. That is because timing affects T slot position, which has to be correct for the carb to properly function; this, in turn, affects idle vacuum, which becomes important for PV selection.