Thoughts on Cooling a Stock 383 HP Barracuda/Dart.

The thermostat has nothing to do with how hot the engine runs. Its purpose is to heat the engine up to operating temperature as quickly as possible and regulate flow.

In other words, a 180 thermostat's design is not to make an engine run 180, nor a 190.......and so on.

190-195 is generally the correct thermostat to run. This allows the engine to get to its operating range quickly to allow for quick warm up and to get the engine out of the range where it will be too cool.

Running an engine too cool will cause premature wear and does not properly get contaminants and moisture out of the oil.

If you're having trouble with an engine running too hot, the problem is in the rest of the cooling system and not the thermostat, unless of course the thermostat is stuck closed.

You perhaps don't have enough radiator, or it may be restricted.

210* sitting in hot weather in traffic is actually a perfect temperature for an engine to run.