[RonC]

The purpose of the thermostat is to keep an engine at its ideal operating temperature of approximately 160 to 195 degrees. Cylinder wear is reduced when an engine operates between those temperatures. The Model A cooling system was not designed for a thermostat. Adding a thermostat is a design change. It changes the cooling fluid flow when closed and when open as the orifice is smaller than the hose. A thermostat will allow and engine to get from zero to 160 faster than without one so yes less wear when cold. The question is what operating temperature will your engine be at with versus without a thermostat? If it does cause your engine to run above 195 more often than without then wouldn't you be causing more cylinder wear?