Large RPM and Vacuum drop when shifting from park to gear
A ported advance does increase timing as you tip-in the throttle -which is exactly what you don't want.
I don't want to start something;
but,I gotta disagree with this; I think it needs to be qualified.
But I also get what you are trying to convey, and
It's pretty obvious you know your way around timing controls.
But it seems to me that you are not speaking to how all streeters are operated. like;
I have a manual trans,
At Part Throttle;
my 367, at 180psi, generates an excessive amount of torque way down low.So I have to be careful to NOT run too much timing down there, because the car then wants to get to bucking. So I purposely have a small amount of idle-timing; just 12 to 14 degrees.
Then it ramps up to 28*@2800, then to 34* at 3400.
But my Vcan , is able to add 22* at any time. So cruising at 2800 it could be pulling 48*. This engine at WOT will blow the 295 tires off thru two and three gears, so I am not interested in max anything.
But one thing I like to do is idle thru the burger joints at 4 mpg, parading, I call it.
To get down to 4mph with 3.55s and 27s takes an in-gear and driving rpm of 550rpm. To do this, without bucking, takes 5* of advance. This CAN NOT be done with 22* of full-time Vcan operation; my t-slot sync would be impossible to drive.
Yes I could achieve some/most of that with full-time manifold vacuum.
But the thing I cannot achieve is a sufficiently low idle speed, whilst having an appropriate transfer slot sync. . Nor could I ever drive it at low speeds without riding the brake or slipping the clutch; AND, it would be impossible to parade with, a thing I like to do.
Automatic guys have an easier time of it; just throw stuff at it until it knocks. That don't make it right.