Technical Information Low Temperature Thermostats
It is very important to use the correct temperature thermostat in your cooling system, as the water temperature plays an important part in closed loop fueling operation.
Many people think that running a colder thermostat will keep their engine from over heating or that it will give some performance gain. This is incorrect and will just keep the engine from properly warming up. The engine should be between 185 and 200 degrees F when fully warm.