A little clarification on adjusting idle air mixture on eddy carb

With a manual trans;
Depending on your overall starter gear,and your cylinder pressure;I highly recommend not to try and run the Vcan full time off the manifold. Your low speed will get too jumpy as the Rs fall, and it will not pull itself very well, at low mphs. This is because the pressure pulses will be too strong. Instead, as the Rs fall to under 650rpm in gear, you want to retard the timing, down to perhaps 5* at 550. This will weaken the pulses. The engine will lose power,and smooth out. She might want a slightly higher idle speed screw setting in compensation.
Of course, with a mechanical D this is not possible to do. But if yours gets jumpy, now you know why.
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This is why I only run 12 to 14 idle-timing. Then I run a lot of advance in the Vcan to compensate.I also run a dash-mounted, dial-back, timing device (with a full range of 15*) so I can retard it as far as I need to up to ~8 degrees. In this way I can get the idle down to 550@4mph, a brisk walking speed. On flat,level,hard ground it has just enough power to pull itself.
These things gain importance as the cylinder pressure rises.
When the engine is cold she wants a lot of advance. If it doesn't have a choke, you gotta baby sit the throttle for a couple of minutes. Normally the choke also increases the idle speed, sometimes to the point that the Vcan gets activated for several degrees. Here is another place that I use the Dial-back timing device; this time I dial in 7* for a total of 20ish degrees. And set the low-speed circuits a tad rich. In this way, I don't need a choke, and it is GONE.
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Here's how I set the mixture screws on a manual trans; fully warmed up of course. I put the carb up on the fast-idle cam at 1800 rpm or so. I put the air cleaner back on. Then with the engine at ~1800 I set the mixture screws for the highest rpm. Then I add 1/8th turn rich for a Holley and 1/4T for anything else,kick the fast idle down, and shut the car off. The extra 1/8 T is for cold-idle compensation, during the warm-up. Then I screw the mixtures screws in counting the turns as I go. Then I add the turns together and divide by two, then reset the screws to that average number.
If the car won't idle after this, I might bet a dollar the throttle valves are not far enough up the transfer slots. Rarely are they too high. So crank up the curb idle until the engine idles sweetly but too fast. Then retard the stinking timing to whatever idle speed you want. Then fine tune the idle quality one last time with the idle SPEED screw, now adjusting idle fuel with transfer slot exposure.
In this way the mixture will be pretty close @1800 in low gear, for most of the time. At 1800 the Vcan should be on line as well.And the D will have cranked in about 6*. If you had the initial finalized at say 12*, now you have 18* plus Vcan . Mine has 22* by this time, so my total is 40*. Because of this, I can set my carb pretty lean at 1800rpm on a warmed up engine. But this does not help the engine one bit when she's cold, and neither does setting the mixture screws any other conventional way. And nothing irks me more than a neighbor babysitting his carb for 5 minutes on a cool morning, so I don't want to be the guy blipping the throttle with twin 3" cannons pointed his way,lol.
BTW, I use 1800, because with my combo, 1800rpm gets me the following cruising speeds; 13,21,29,41,52.I have it geared this way because the pipes are singing a relaxing melody at 1800. Some of these speeds correspond very closely to popular posted cruising speeds, making pulling fuel economy as good as it gets.. If you have 3.55s and 27" tires, you'll be similar. If you have 3.23s , then your rpm of interest might be 1650 to achieve those speeds; but your Vcan may not be on line yet, which if it's not,is gonna suck for economy. To prove it is or is not, you will have to Tee into the spark-port and run a vacuum gauge up to the windshield, and take her for a ride, paying particular attention to the rpm/vacuum,at the common cruising speeds.
Of course if you don't care about fuel-economy, then I guess none of this is relevant.
In any case; Happy HotRodding.