Thermostat question

Sorry if this is a dumb question, but three thermostats are offered for my limousine, 160 degree, 180 degree and 195 degree. What should I consider before making a choice as to which one to put in my car?

As always, thanks!

The factory service manual says that the thermostat starts to open at 173* F to 177*F, and is fully open at 198*F (approximately 1/2"). This would indicate that a 195 degree thermostat was originally installed in the engine.

in the good old days you changed the thermostat in the spring to the summer one (160) then in the fall back to the winter one (190). now they figures if you run the engine hotter it's sub post to make better mileage. the 10% etoh kills that Ida. like Paul said the 190 was most likely the one that came from GM. but if you plan on parading the car it might be better off to use the 170 one.

What would I do without you guys? Thanks

John, what year is your car? If it is a late model with a computer control system the lower temperature thermostat may trigger a trouble code.

The calibration is set to run within certain parameters of engine temperature.

If it is not a computer controlled engine, I would go with the 180 degree. Remember too that a engine has to "burn off" condensation that is generated as a normal condition of combustion and an engine that runs too cool may not evaporate the water inside. Water in oil is a possibility then. And water is not a good lubricant.

Another thing is that engine oil should also be at normal operation temperature, a 160 may not allow it to get warm enough to flow as designed, kind of like running a very heavy (70w) oil in a stock engine. It may not flow to all areas with adequate lubrication to all metal surfaces allowing scuffing and excessive wear of barings, rings and on and on.

180

i run 180 and am good even in 100% traffic. if its got a carb, run 180. fi and computer cars run 195. my story anyway as it works for me. i do run a moroso 175 in my old vette. diffrent spring for a all open at temp.

When the outside temperature is in the hundreds, you could run without a thermostat and not see the difference. Thermostats are for cars where the temperatures are lower than you experience in Texas. I can remember when if you bought a car from Texas up North, you would freeze in the winter, since they were all built without heaters.

If I was going to not run a thermostat I would at least add a restrictor to the cooling system. A engine under the "right" conditions without a thermostat could overheat. The thermostat also serves another purpose, that is to slow the flow of coolant down thereby keeping it in the radiator longer. The longer it is in the radiator, the more air flowing over the core, the cooler it gets.

Restrictors are in common use by drag racers, either factory made or by removing the "works" in a thermostat.

I would add a restrictor to my own car if running without a thermostat.

and i remember buying cars from up north and no ac. first one i bought without ac was because i didnt look since i assumed all cars had ac. didnt make that mistake twice though. learned my lesson. try selling car or truck here with no ac. wont happen. even a t**d has to have ac or you will own it for ahwile. today 100 degrees and 100% humidity. feels like 110+. break a sweat walking to the mailbox.replacing a bay window today so ac will not be much use. i run a 5 ton unit and its not enough on bad, hot days. you get acclimated after enough time but its still miserable in the summer. 5 showers a day to cool off. just jump in and 5 minutes later start sweating again. never knew ambulances were born with no ac until later in life. just too damn hot!!!!!