Cold start and driveability has come a long way since the 50's. The carb atomizes fuel/oxygen and works well when warm. However, once atomized fuel/oxygen hits cold air it becomes a liquid again. Liquid fuel does not burn. The vapor/atomized fuel/oxygen does burn.The engineers worked on what is called EFE or early fuel evaporation. To obtain good cold start and driveability the engineers needed to find ways to introduce warmth to the carb to keep atomized fuel/O2 from returning back to liquid form thus not burning and providing misfire, stumble, stutter, stalling and overall poor performance when cold. Our nailheads have absolutely none to speak of. Sure, there is a choke that holds the idle high and kicks off as the heat from the tube attached to the exhaust manifold warms the coil inside the choke assembly. But that is it. Over the years the engineers developed hot air tubes from the exhaust manifolds that fed directly into the air filter housing. Ports in the intake manifold that allowed hot gases to warm the base of the carb. My 401 has this port in the intake manifold. Intake manifolds that have passages that allow hotantifreeze to warm the base of the carb. Electric grids that warm the fuel as it passes through the intake(throttle body injected engines). And finally, direct injection that the computer does a great job of controlling. Much of early EFE is not required any longer.
Nailheads are not fond of the cold. I let minewarm for a minute or so then go sincedriving does make the engine warm faster. She will still sputter and such until warm. Plus, she is some old bones. Can't blame her.