Join Date: Sep 2000
Location: Washington, Michigan USA
A thermostat, assuming it's operating properly, has virtually nothing to do with overheating - it just provides faster warmup and regulates coolant flow. The Robertshaw 330-180 is a good high-flow thermostat - I've used them for years. The temperature rating of a thermostat is the temperature at which it BEGINS to open - it isn't fully open until 15-20 degrees above that. Cooling capacity is determined solely by the radiator at highway speed, and by the radiator, fan, and shroud working together as a system in low-speed traffic. If you have a cooling problem, a lower-rated thermostat won't do anything for it.
'69 Z28 Fathom Green