Doesn't really matter what the temp rating is...the engine is going to run hotter than that anyway. Otherwise, the thing would never open, or it would just sit there and go open/closed/open/closed/open/closed.
As I've said(and others too), the rating on the stat is OPENING temp. A 160* stat is gonna be open at 160*...a 180 will be open at 180...period. Having a 160 degree stat doesn't mean your engine will only run 160 degrees all the time...that's physically(and thermally) impossible. It just means the stat will open 20 degrees cooler than a 180 stat....that's it. The engine is still gonna continue to create heat. It's the job of the
cooling system to control that heat...NOT the thermostat.
Around here, an engine with a functioning cooling system, with a 180 degree stat, will average around 200-210 degrees coolant temps, depending on the cooling system design. Installing a 160* stat will NOT lower that engine operating temp....but it will start coolant flowing thru the radiator sooner.
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Joel Adams
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