225 stalling

I guess in 62 they didn't have a PCV system. Is the carb also a 62 model?
Cuz if it's a post 68 it will be calibrated for a PCV. If you run a PCV carb without one, you will be too far up the transfers at idle, with the factory timing. And your mixture screws will be screwed in too far. This will make it idle, but lean at tip-in, causing a sag or hesitation. If you crank in some timing, then you can sorta get the fueling right, but then sometimes that puts the engine into detonation under load.
So the take-away here is, that if your carb has a PCV port, you should figure out a way to use it, and get rid of the road-draft tube...... or go back to the 1962 calibrated carb.