Looking to replace the thermostat on my 72 Cutlass 350. The car does not have factory A/C or a fan clutch and I am concerned about it running a little hot. Plan to replace the stock four-blade fan with a OPGI seven-blade. But I'm wondering what setting thermostat to drop in -- 160, 180 or 190? And any preferred brand?

 

I prefer the Stant Superstat 180*. Please note that the thermostat has nothing to do with the maximum operating temp of the engine, it will be based on cooling efficiency of the system. The thermostat regulates the minimum operating temp only.

 

This should be printed on the back side of every thermostat box. Then people would stop trying different ones in the hope of fixing their overheating problem.

 

I agree

 

Sorry, Other Eric -- thought I had both of you guys providing answers. Apologies to you, too, Jaunty, if offended by being called either Eric. While I've got you wiser heads answering the thermostat issue, let me ask about a related issue. As I mentioned, this is a very stock 350 w/o factory air. No fan clutch, no fan shroud, four-bladed fan. So, what I'm thinking about is getting a fan shroud installed and a seven-bladed fan OPGI offers when I get the engine pulled to get a top-to-bottom gasket and seal replacement. I see where the Other Eric already suggested taking a look at motor mounts to make sure I don't wind up with a fan blade hitting the bottom of the shroud. What do you boys think of my plan -- wise or overkill? I should mention that I plan to eventually put in an Old Air or Vintage Air a/c unit some time next year. Part of my Year Two capital expenditure plan.

 

We get a lot of thermostat and overheating questions on here. Jaunty's statement is because most people have no clue to what a thermostat actually does. I answered your duplicate question above you sent by pm.