Idle Issues...

You need to keep in mind that there are all kinds of timing targets
-The most important is power timing. This is the timing that the engine will see when the engine is at full throttle, and fully loaded. If this timing is too much, bad things can happen to the engine. If it is too little, performance will be sluggish. If it comes in too early or too late, performance will suffer. The window of "sluggish" to "best" is quite small; perhaps as small as 4 to 5 degrees.Happily this power-timing has been worked out and refined by much smarter persons than me, to fall into an even narrower window of 2 to 4 degrees. So with that in mind I would suggest to set your maximum power-timing to 34* plus/minus 2*.
-Now the power-timing is the maximum that your distributor is able to provide, and that is with the vacuum advance system defeated. The maximum. Not how much it provides at a certain rpm, but the maximum period.
-So if you have a dial-back lite, let's get started. But if your lite is conventional, you will need to mark your dampener all the way out to 40 degrees, or perhaps 60* if you decide later to fiddle with the Vcan. Timing tapes are available to make this simple.If you decide to tape it, you ought to prove the TDC mark is true TDC...... So, rev it up, til the dizzy stops advancing, and set it to 34*BTDC. And then note the lowest rpm that the timing is still 34*.Call this the start point.
-Now after the power timing is set, the idle-timing could be way out to lunch.Not to worry, we'll get to that later.
-Also, be advised that not all teeners accept the aforementioned 34*. So a roadtest is next. The roadtest needs to be done at a low enough speed so as not to get a speeding ticket, but at a high enough rpm to ensure the timing is all in, and that the engine is well loaded. This is usually 2nd gear. But if you have 2.76 gears speeds could be as high as 70 to 80mph. Not good. So if you have highway gears, you will need to start the test in 1st gear. But things happen really fast in 1st gear, so if you have a long,straight, low-traffic hill, that would be best. This test is to find the detonation limit, of your FRESH FUEL,(of the type and grade that you will be using on an ongoing basis). Pick your test area and time carefully.
-So, here's the test.You will be accelerating briskly to about 200 to 300 rpm before the the "start point", at which time you will floor it.You will be listening intently for the tell-tale knocking sound.If you do not hear the knocking sound, you may continue the test at WOT, to 4000rpm or the speed limit, whichever comes first.If you hear knock during the test, get off the throttle.
-No knock, means success. Any knock at all needs to be dealt with.Do not be tempted to floor it right from the get-go.This test is not for that. We can get into that later.
You will also be watching for a carb lean-out during the test.If you feel the car accelerating briskly for a bit, then nose over, and feel it's rate of acceleration per time period is slowing, well, we will need to address that first. For this test to be valid, the fuel level in the bowl needs to be stable.
-Okay,Put the tranny in manual low, and it's go-time!
TTYL