Re: Atomic 4 cutting out in forward.
Several things can cause this:
1. dirt in the carburetor ... principally on the 'emulsion tube' - controls the air/gas ratio under varying engine speeds. Any amount of dirt in/on the teeny orfices of the emulsion tube can cause great shifts in fuel/air ratio.
2. Blown head gasket ... usually between 2 cylinders (3&4). Do compression check with the engine HOT and then when COLD.
3. Ignition coil is beginning to fail. .... especially common on transitorized 'points' systems where a HI TEMP coil was not used in the 'changeover' from mechanical points to transistorized.