67 Dart 383 high temperature question

Unless you are trying to get the maximum HP out of your engine, do not run a 160 degree thermostat.

Engine wear DECREASES as temperatures rise, an engine running at 160 degrees will have four times as much wear as one running at 180. Clearly if an engine becomes too hot can lead to serious problems, but for the most part anything under 200 degrees is acceptable, some new cars are designed to run at 210.

Personally, I put 185 thermostats in all my cars, temperature will fluctuate between 180 and 190 all day long as the thermostat opens and closes. In traffic it will stay right at 190 and not climb, this shows that your fan is adequate to pull sufficient air through the radiator at idle. If I pull a long hill the thermostat may climb to 200 degrees, at I've only seen it hit 210 once and I shut off the A/C which immediately brought the temp back down to 180-190.

Finally, be dubious of temperature gauges. They should be used as a reference only. For example, if the temp gauge shows that the car is running hot, and you pull over open the hood and the motor isn't radiating a ton of heat, you might have a gauge that reads high. Get an instant read temp gun and point it various parts of the engine to confirm just how hot the motor is. For example, read both the top and bottom of the radiator, read both the left and right exhaust manifold (they should be about the same). This will give you a good indication of how hot the car is actually running.

Regards,

Joe Dokes