tuning

Lots of RPM drop putting it in gear. Make sure it's not dropping timing when put in gear. It shouldn't at such a low RPM.

I prefer ported vacuum to manifold.

my 2 cents, set initial around 16-18 minimum, especially if it starts easily when set at least at that point. Then curve the rest. I believe those distributors require you to bend a tab to adjust mechanical.

Find out where it stops advancing. You may need to look into some micro springs at Ace Hardware or find some springs that will work from other distributor set ups.

Fuel pressure can be an issue with ede carbs. Look down carb to see if fuel is dripping off the boosters. If you see fuel dripping, you have issues!