Proper Thermosts temp for 318

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soonercruiser

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So, the old man and son who worked the engine in my 67 Barracuda have put in a thermostat that never gets above 150 degrees.
Even on 80 degree days, it was barely above 150 sitting in traffic.
And now that the daytime temp is in the 50s, not even near 150. And so, very little warmth from the heater.
My feeling is (rookie) that that is too low an operating temerature for the 318.
What's you take?

I've seen this discussion on another MOPAR site.
"As others have noted, go with the 195 thermostat. The industry moved away from 160 degree thermostats years ago (1950s?), and away from the 180 degree thermostat (IIRC) somewhere in the 70s."
 
I run 160's in my classics that see no use in the winter. 180 in those that "might". Factory recommended in our daily drivers including the winters
Also, verify your heat gauge is working accurately
 
Verify gauge and run what he factory service manual says. In the 67 FSM it specifically says do not use a 160 deg thermostat

BTW the thermostat ONLY sets the low temp the ambient temp, load and the cooling system efficiency sets the upper.

A lower thermostat temp does not change the efficiency of the cooling system.
 
It depends on the build and what you're doing with it. At this point, with the total plethora of information given, how the #@$! do we know?
 
I run 180° stats. I think the engine should get to operating temperature. :lol:
 
Having lived in South Dakota, the quick fix is a partial cardboard block in front of the radiator. Had a 170 slant six that ran very cold.
 
160 can be too cold if the radiator works well. Everything Mopar went to a 195 thermostat in 1969, but most aftermarket thermostats do not flow as much as factory thermostats did in the 60's. 180 will give you a better runnning engine, unless there's other issues that cause heat or ping.
 
I lived in New York 99% of my life. So cold I understand.
I used to run 180* thermostats. Heat was fine.
Switched to a 195, heat works even better.

A hotter engine doesn’t perform better, but in a daily driver where your not overly concerned with performance but more so with defrosting your windshield and being warm inside the car when it’s cold outside, I certainly suggest a 180* at a minimum and liked the 195* better.
 
I have a 195* thermostat in my rebuilt 318, that never sees winter driving (salt used on the roads here in metro-Detroit).
 
On a street engine I wouldn't run anything cooler than a 180 and my preference is a 195. Engines that come up to temp quickly last longer, use less fuel, and stay cleaner inside. Nothing is gained by running the engine cooler. As others have mentioned, some of the low cost 54mm thermostats out there don't flow particularly well. There are plenty of high quality thermostats out there that cost two or three times as much as a cheap one. Spend the extra $3-6 and buy a good one.
 
FREAKIN-A! Quality parts prices are forgotten about after many years of service due to there longevity. I can attest to this for sure!
 
Thanks for all the responses.
Sounds like I should go to at least 180.
Although the summers are hot and long here in Okieland!
But the great aftermarket rad should handle it fine.

Lived in Duluth, Minn, my first assignment in the Air Force.
Cardboard wasn't even enough there.
I had a power line across the alley to where we parked the car, hooked up to a tank heater on our 1970 Dart.
Most of the winter, all I could see was the top of the pole I ran the wire to.
NEVER MORE! :(
 
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