318 stalling from idle

My guess is that the transfer slots are too far closed;
One way to tell, is if the mixture screws are open significantly more that 2.5 turns. If so;
Increase the idle rpm, then retard the timing, little by little, until it goes away. then close the mixture screws down to about 2.5 turns and repeat.
Other possibilities are;
that the fuel bowl is not properly ventilated, or
that the WET fuel level is low, or
that the fuel is stale. The fuel should be clear as water.