It can't run cooler. All a thermostat does is determine when the coolant can run through the system. Anything over the designated set point of the thermostat is beyond it's control. You'd need a bigger radiator for it to run cooler.

 

You are exactly right.

Running a 180 tstat requires changing the tune on the PCM to accommodate it.

 

well the needle stays lower is all i know, maybe previous owner used crap coolant or water then.

 

If the thermostat lets the cool radiator water in and starts circulating sooner, wouldn't the engine run at the temperature that the radiator is cooling at?
All it should change is the air to fuel ratio since the PCM is detecting that the engine is running too cold.

i.e. radiator can cool faster than the water is heating up at?

 

Correct. For the most part. The thermostat can only control the minimum temp the engine runs at. If the cooling system can't keep up with demand, then engine runs hotter.

 

Yes, the air/fuel mixture changes...and to what direction do you think that is?

The engine is not running at the temperature of the coolant. The oil temperature would be metric for that, not the coolant temperature. The gauge in the cluster is only of what the coolant is at. The PCM has parameters to look at based on it's value.

Here is a link to not repeat b/c some good people already captured it...which SHOULD have been searched for my the OP, getdown!!

https://dodgeforum.com/forum/2nd-gen...hermostat.html


Pay attention specifically to what DrewActual posts....