The engine's thirst for timing, I think is telling you it needs more time for the fuel to find oxygen to react with.So Yeah I would be looking for a lean situation. How are the float bowls receiving venting?
I’m not sure what you mean. It runs poorly at idle and rpm with 18*/33*, if I retard ignition to 10*/23* it runs slightly better. By better I mean it has more consistent vacuum and rpm.
