I think most that do this rev the motor to 2k or so to get a little more accurage reading on the HB...or atleast its easier to set as the timing light flashes more with the higher RPM.
The timing reading stays the same when you do this. You remove the SPOUT connector, set the timing where you want it targeted (26*, 28*, etc) and leave the SPOUT connector removed.
Now you run around with the timing where you set it. So mine was at 28* at idle, at 6K RPM, and every where in between. THe EEC had no control over it.
And since I think I'm misreading the question, I set it at idle. Then ran the RPMs up and watched that the timing wasn't changing and was where I wanted it.
With good gas
You'll make the most wot hp with a total amount in a range of 36 .....
give or take a few.
This is said disregarding any advancement methods no matter if we are talking
about a little silver box we have today or even old school methods such as
bob weights or a vacuum canister hanging off the side of a dizzy.
Again this is with high octane and a race or wot application
Now ... this is not gonna be all that practical for a street application
In all honesty ... these days the spark is controlled by the pcm and
during very light load driving conditions, you will see spark values
well over 40
RPM is also in control of spark values
When one does the pcm-less timing thing
They don't get those benefits
Might ... again ... Might ... make more wot hp
but
Won't run as smooth during most other driving conditions
Hey ... try it and see
Just don't go hog wild on the spark at first
especially
If all you got is that weak Kool Aid stuff they call gas up North