total timing reading accurate with no load?

Some photos showing throttle plate's relationship to the transfer slot in this post
Carburetor Question - Is this a good call?
The portion of the transfer slot above the throttle is at higher pressure - and the portion below is at same pressure as the idle port.
At idle - fuel comes from both! The mix screws only control the portion through the idle port.
As the throttle opens, a larger portion of the fuel comes from the transfer slots. Off idle performance depends on the throttle and transfer slot relationship to be correct - its like a variable jet and variable airbleed combined.