What temp thermostat to use?

[oldbee]

I guess it really depends on where you live and the setup you have. i can only tell you about my experience with a dead stock '69 RR 383 in the Miami heat. It was a show car and I wasn't able to use any modern cooling beyond adding some Water Wetter to the distilled water (no antifreeze needed) I was running. My best results for my particular climate were when I completely removed the stat and allowed the coolant to circulate continuously. But if you are able to use upgraded parts and you don't generally sit in traffic, that might not work. I just wanted to present my own real world results for you.

Just to muddy the water a little, I always thought at least a gal. of a/f helped a little with cooling? Better heat transfer?

 

[66Hemi]

Elev is an issue for boiling pt, timing, performance, etc. Am @ ~ 5800'. My '69 R/T was running WAY hot w/ 180 @ 35 deg adv & 3200 rpm (~70 mph). Swapped to 160.
180 should be good for the low elev of IN

 

[Ranger16]

Elevation would be a factor if the system wasn't under pressure, but being pressurized takes elevation out of the equation.

 

[Bill Monk]

195 and use a good water wetter like Lucas or Red Line. Too low a thermostat and you can get unvaporized fuel in the bottom of the intake and can also cause engine wear. BTW, if the thermostat is opening when it is supposed to, it won't cause overheating any more than a 160 will when in traffic on a hot day. That has more to do with the radiator, correct shroud, water pump and clear passages in the block.

 

[57tbone]

180 is the best but in southeast Louisiana I have to run 160 and still run 180 or higher in July and August. All the goodies you have in your engine makes a difference sometimes also. Trial and error was what I had to do. Good luck!

 

[1967coronet440]

Got a mr gasket 180 thermostat and gasket from summit, gasket is real nice.

 

[GetX'd]

I have a weird situation - I had a 160 in there and the engine seemed to be running too cool. I swapped it out for a 180 and now it runs cooler!! I think my gauge must be faulty. I bought one of those infrared laser temp guns but have not tested it out yet. What else could it be.... ?

 

[miller]

What else could it be.... ?

Thermostat stuck open?

 

[The Shoe]

Got a mr gasket 180 thermostat and gasket from summit, gasket is real nice.

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I've recently had two brand new Mr. Gasket thermostats go bad. One I installed in a customers car and it never opened. I had a second installed on another project, removed it and slowly heated it up in some water on the stove and the water temp got to 270 degrees and the stat never opened. Ended up replacing one with a new Stant and the second with a Robertshaw and have had no problems since. Both were 180.