180 or 195 thermostat?

[skillet]

Which is better for a "69 350 auto, 180 or 195 thermostat(or what was stock)? Thanks for any comments.

[68GMCCustom]

I prefer a high flow 180.

[Eichorst69]

I agree, 180.

Rob

[Ole Blue 68]

Depends what you're looking for...I run a 180 but if you're hoping to improve MPG you might want to consider going higher.

[chevy72blu]

There really isnt a right answer, more of a preference thing. The important thing is that it climbs to the temp that it opens and then stays there.

I use a 195 in the winter for extra heat from the heater, and 180 in the summer.

[special-K]

I run 180 to play it safe.195 leaves little margin to boiling point for me.

[El Jay]

I run a 180, but I don't think it matters a whole lot.

The thermostat controls the minimum temperature.
If the engine has the tendency to run over 195, it's going to run over 195, regardless of the thermostat.

[Figment412]

I have a 195 in mine but I don't remember the reasoning for it at that time.

[Andy4639]

The motor has a lot to do with what you run.
For instance is it fuel injected? If so then 195
Carburated 180
Computer cars run hotter temps so a higher thermastat is recomended by most. If you run a lower thermastat it can play hell on the computer trying to compensate for it.
Does the engine run cool in traffic? Then 195 would be OK in the summer & winter you get the heat out of it. If it doesn't then run the 180.

[TonyJohnson]

Originally Posted by chevy72blu

There really isnt a right answer, more of a preference thing. The important thing is that it climbs to the temp that it opens and then stays there.

I use a 195 in the winter for extra heat from the heater, and 180 in the summer.

[Gray Ghost]

I agree with the 180....195 is for newer motors that run hotter. The guy that built my motor said go 180 so that when it runs hot in the summer it doesn't go past 200. He said the motor will last longer that way.

[stope4]

what does the Factory Manual say for 350s? For BB it's 195

[89 crew]

Originally Posted by TonyJohnson

The only thing forgotten is ac. If your truck has ac and has problems keeping its cool in traffic, then the 180 will give it a better chance.

[69heavychevy]

i run a 160, it still climbs up to 180-190 sitting in traffic.

[Boog]

I think whatever temp stat you're running the engine needs to be tuned for that temp range to get the most power and mileage out of it.
After some extended running look at the plugs and see if they're running clean or sooting up a bit. Running too rich or lean affects the running temp too. Ignition timing also affects running temp.

[Stocker]

I don't change mine season-to-season, and run a 195 year-round. Gives me better cab heat in the winter and does not run hot in the summer. Can't recall the numbers, but 195 is still far enough away from boiling in a pressurized system with 50/50 antifreeze.


.02

[stope4]

Surely if GM says 195 then they must be on to something. If everything is working right, it won't boil over. This is true even if it's 210 degrees. Boiling is 212 plus whatever the antifreeze raises it to. Gotta remember antifreeze works in both directions high and low.

[68GMCCustom]

I prefer to runa 180 on the older engines (pre '80s) because I don't feel there is a real need for the extra 15 degrees of heat in Texas weather. I run a mechanical temp gauge and with the 195 stat I'd see temps up to 220* or so just a few minutes after shutting the truck off. With a 180, it doesn't get over 200* after shutting it off.