theoldsrocket

Running my 1972 350 without a thermostat since my intake and upper rad hose gets really hot now it snowed and pretti cold and i started my car after putting in anti freeze for winter it ran at 150 idle 800

jaunty75

Running a car without a thermostat is not a good idea. If it were, cars wouldn't come with them.

Without a thermostat, you car will take MUCH longer to reach operating temperature, and in many situations, the car won't reach operating temperature at all before you've finished your drive.

Running at too low a temperature can be bad for your engine just as much as running at too high a temperature can be. Most likely you car's normal operating temperature is in the 190 to 195 degree range.

If your car overheats with a thermostat in place, you should look for the cause of that overheating instead of just taking out the thermostat.

Oldsguy

It is also bad for the exhaust system, the condensation will never get burned out and there will be premature failure from corrosion from the muffler back.

Rickman48

"Back in the Day", like the '50's, it was common to change the thermostat with the seasons; 180 for the Winter, 160 for the Summer.
Only reason the manufactures wanted 195 degrees was to 'heat up the converters on short trips' [quote from a Pontiac factory Rep] Never installed before 1975!!
i bought a '86 Grand Prix 2+2 brand new, and the thermostat stuck @ 18,000 miles.
All I had was a 180 in the garage, and installed that, as the dealer was 25 miles away.
I was shocked at the difference in both performance and mileage from the 305/200r4/3:08 combination - went from 10 mpg to 14mpg and felt much stronger!!
Next time at the dealer, I questioned the warrantee eligitability of changing it to a 180 - they didn't know, but a factory rep was there, and asked me to wait for him.
When he came down, he didn't know either, but called the factory, who gave him the reason above - only for the cats!
Since I was scheduled for a 'pollution inspection' I was prepared to change it back - but it passed w/flying colors!!!!
Being I was driving 40 miles one-way to work, and changing it back was 'financially detrimental', I chose to leave it in!
When I sold it @ 230k, had only done a water pump, timing chain, and 3 carbs.
Changed from the 200 to a 700r4 @ 120k - worked better!
So, without cats, if you don't need HOT heat in the winter, go with a 160 degree thermostat - the auto parts kids will think you're crazy, but they're usualy in stock!!

bccan

Don't overlook the possibility of having had a bad stat. Try putting one in, either 160,165,180 & see if engine responds favorably. Suggestion - use the Mr Gasket/Robertshaw style stat, they are a much better quality unit than the Stant style IMO. Typically available in the "performance" section of the big chain stores in a Mr Gasket pkg. I have a big radiator in my car & usually run a 160 or 165 (can't remember the detail), it runs "on the stat" except on very hot days in summer while moving slowly or stop & go traffic. On days below 70* I start blocking off part of the radiator core w/ cardboard because it will only get to 160 or so up a long hill or stop & go - otherwise it will run 140-150. 1 piece for 60-70, add a second piece 50-60. Come this time of the year I'll put a 180/185 stat and it will run on the stat except for low load (long down hill stretches, etc) or cold temps (40's or colder) & sometimes I add the cardboard too. This thread reminds me - I gotta change my thermostat today!

theoldsrocket

thanks guys but i don't really drive it in the winter its only for the summer and is stored mostly in winter so i think 165 would be good to go?

bccan

Throw a Mr Gasket 160* in there & see what happens. If everything in the system is even close to proper, it should work fine.

theoldsrocket

http://www.summitracing.com/parts/MRG-4363/?rtype=10

is this one fine for it?

theoldsrocket

i think i pulled a 180 out of it should i put a 180 or 160 note car is for summer and only warming up in winter

Lady72nRob71

These are available at Autozone, too.