What is all the talk about the 180* degree thermostat. Is there any advantage for my car? My Bonneville is a daily driver with 145,000 miles on it. It is not supercharged. Will changing from a 195* unit to a 180* unit help me out?

What advantages are there?

Thanks for your help.
Andy in MI :?:

I know that my car wold frequently push 220+^ in the summer time. That'* a bit hot for our engines. The 195 will be just fine for the winter, but once summer comes around it wouldn't hurt to installa 180^. Since I haveinstalled my 180^ I have had ALOT better engine temps, summer and winter.

There really isn't any disadvantage to a 180. Although, I wouldn't recommend going to anything lower than that (like a 160 - too cold). You'll find that the 180 heats up just as fast as the 190 or any other t-stat. The difference will be when it is hot out that it takes longer for the car to overheat. If you're sitting in traffic it will buy time beofre the engine heat rises high enough to be concerned about. Most members here that have switched are glad they did.

Ok guys, will someone please explain the heat dynamics involved in a 180 degree thermostat allowing my engine to run cooler that a 195 on a hot-*** day. Let'* assume that the water jackets and radiator are in good condition, allowing max water flow, and that we have a 50/50 antifreeze mix.

Let'* say I have a 180. As the engine temp rises and reaches 180 the thermostat opens allowing max water flow. Now suppose the ambient temp is hotter than Hell. How is my engine going to be maintained at 180 degrees, or even 190 or 200 if the engine will normally reach that operating temperature and above before the fans kick on!? Isn't the thermostat going to stay wide open allowing maximum cooling anyway. A 180 thermostat doesn't have a larger opening than a 195 does it. Doesn't appear to have. I DO know that if I increase the cooling surface area of the radiator (ie- larger radiator), THAT will help remove extra heat, allowing the engine to run cooler, but a thermostat that opens at 180 as opposed to 195?

I have noticed that on a cool day if I run my stock 195, the temp will hover around that point, AND with a 180 under the same conditions, the temp will hover around that 180 point too! But once I get a nice hot day...........up goes the temp until the fan kicks on. Then the temp drops back to that 195-200 point or even down to around 190 with the 180 thermo, BUT IT TAKES THE EXTRA HEAT DISSIPATION CAUSED BY THE FAN/* TO HELP THAT THERMOSTAT ALONG.

I've also found that turning on my AC gets the temp back down to that 190 or 185 in a hurry (sometimes preventing temp rise altogether).

What gives with the 15 degree lower thermostat opening point? I just don't get it and have yet to experience lower operating temp on a hot day with the 180.

Thanks for any explanation you can provide.

the only thing is if it gets cold in your area change back to the 195 i didnt so my car takes forever to heat up and i got i keep the ECC on 90 to feel comfortable

You really thought through this...
If you change to the 180 you are correct in stating that your fans will not come on any earlier, therefore the engine will heat up to the point where the fans come on and it will only cool it to a pre-set point (regardless of the thermostat installed). When you operate your A/C, the fans are switched on and will remain on to allow air flow in order to take the heat out of the A/C unit. Although there is additional load on the engine, the cooling system is efficient enough to handle the extra heat and load. If you have the 180 stat in, and the fan is constantly running, the engine temp will drop to the point where the stat will begin to close (in that case, 180). If it is a hot day as you suggested, it is still cooler than 180 outside, and your cooling system will still reduce the engine temperature.

If you are running on the highway, you will see the 180 stats effectiveness regardless if the A/C is on or not. The air flow through the front of the car is ample to keep the thermostat opening and closing around the 180 mark. If you have the 195 you will see it operating in that range.

All of this said, you can get performance stats that do allow more coolant flow, however, that is not going to make any difference in normal operating conditions.

Does this help or did I just create confusion?

bonnevilledad is right on.

Just think of it this way (really simplified), there is a 15^ difference between a 180 and a 195. That'* 15^ worth of time that coolant is allowed to run thru and try to cool down the engine vs haveing the coolant sitting there still retaining heat. If the coolant it moveing thru the system it is cooling better than if it sitting stagnant.

You're not gonna see some miraculous cooling with a 180 vs a 195, but it just gives you a little more protection against overheating.

Like I mentioneed before.... with a 195 installed my high temp in the summer was usually around 215-230^. After installing the 180 it dropped dwn to 200-210^. That little bit of extra cooling time was there long enough until I got going on the road again to let the radiator do it'* job.

I agree completely. I have seen the same result with mine. I also live in a mild enough climate, that I can run a drilled 180 year-round.

I also agree.

Will, since I replaced my 4 holes 180 with a new 1 hole 180, I have had no problems or codes...even with temps close to freezing.
It'* only a few degrees colder where I live 400 mi north of you.

That 400 miles cost you a hole!

I'm running two 1/16" inch holes now. My 4-hole was too extreme. BTW for the rest of you, this is still vastly preferred over a 160° stat.

You cannot go wrong with a 180 degree thermostat with 2 1/16" holes drilled in it. It can't do anything but help your engine. All I can really say is that I highly recommend it!

Shawn