I guess thermostats must have changed substantially from my younger years. Back then, the only thing the temperature rating meant on a thermostat was the temperature at which the thermostat would OPEN. Everything else was exactly the same on those thermostats. They didn't allow MORE coolant to pass while opened, and didn't change the running temperatures at all. A 180 degree thermostat would open at 180 degrees. A 160 degree thermostat would open at 160 degrees. Once the coolant reached full operating temperature, it didn't matter what sort of thermostat is in place.
