160 or 180 T-Stat truth or myth

I currently have a 160 t-stat but it's running on the high side in the summer from 190 which is ok to upto 230 which is abit to high for my taste, in the winter it stays around 160 to 180 which I hear is abit low (160)... I read in hotrod magazine that it's a myth by using a lower t-stat to lower your engine temp... so my question is that would it make my tempurature more steady if I put a 180 t-stat in there? or would it go even higher? I have a universal griffin aluminum radiator installed already. when money allows I plan on getting a oem fit aluminum radiator. till then I'm just thinking on the t-stat... I'd appreciate your comments/suggestions. thank you.

 

Good question. I don't know the answer.

I run a 160 with a griffin aluminum radiator, and it runs at 180-185 in southeast texas 95 degree weather, high humidity, stop and go traffic. Dead on 180 when I am on the highway.

Takes a while to warm up in the winter, but it runs 180 then too.

When I was having overheating issues with my stock radiator, I tried to run without a thermostat, and it actually ran hotter. Apparently, the water ran through the radiator too fast and didn't have time to cool down.

I now run a BeCool 160 which has a higher flow, but not free flow.

My personal gut feeling is 160 or 180 won't make much difference. It will open when the engine gets warm, and then when open, it will get to whatever temp it is going to run at, and hover around there, regardless of what temp it opened up at. It just may warm up slower if it opens up earlier (ie, at 160).

As always, I am open to argument, but I feel that once it is open, it is open, and then it doesn't matter what temp the thermostat is set for. It WONT cool down below 160 and close up, unless you are in cold climes.

 

This will likely end up being a pretty interesting thread. Lots of conflicting beliefs around radiators and cooling systems.

 

Are you sure about that? The coolant ran through the block too fast and didn't have time to absorb the heat. This is why a flow restrictor is used in racecars...I hear that computer controlled fuel injection engines like to run around 210*-220* whereas carburetor engines run better at 160*-*185*. Every engine has its on personality...I can tell the temp of my engine by the way it is running. It has more pep at 175-180** and it falls on its face at 190*-200*.

 

Car Thermostat Problems ...:Handshake

 

If you are running a 160 T stat and your engine runs at 190 normally.The stat is never closed after warm up.There fore you have no coolant flow regulation.Same as running no T stat.Coolant wont spend enough time in the radiator to dissipate the heat into the rad fins/tubes where it is exchanged with cool air.Put a 180 stat in there and see the difference( bet it wont go over 200 if you have a good radiator) Engine temps below 180 Deg cause premature Cyl bore wear and piston skirt scuffing/collapse.

 

Once again what he said. Too cold = wear. Your engine shouldnt fall flat on its face at 190-200. Thats optimum range.

 

I run a 190. I have a 1406, HEI dist, and Im runnin it that high to help burn the gas(carb is leaned out all the way, and my nose hairs are still falling off!)

 

Sounds reasonable, but my temp gauge is reading water temp, not engine block temp, so when it was overheating, it was the water that was getting hot. I assume the block was getting hot too, of course.

I love threads like this. You get everyone's point of view, and most of it makes pretty good sense. I just might learn something from it!

 

Coolant sensors are located on the engine side of the stat to read engine temp regardless of flow or stat opening. You arent running water are you??

 

the reason that the coolant over heats with no t-stat is that its moving to fast to disapate the heat. heat moves towards the cold. so as the motor builds heat the heat is moving into the cool coolant. there is more coolant in the motor than there is in a radiator. with the coolant being unrestricted it will just keep asorbing the heat. that is why it will over heat and not run cooler with out the t-stat.

 

If the rest of the cooling system is capable of maintaining 160 or below, a 160 'stat will run your car at around 160 and a 180 stat will run at around 180. If it's not, then the only effect it will have is how soon it warms up.

And I've been hesitant to say anything about this until now because I know I'm gonna start a big debate here, but this business of "water moving too fast to cool the engine" is a widely held belief that is just not true. I keep hearing this all the time from people who usually know what they're talking about, but no matter how many smart people believe it, it's wrong. You can move the water too slowly to keep up with the increasing heat, but you can't move it too fast for the water to cool the engine, or for the radiator to cool the water.

I think this comes from people saying it's bad to run without a thermostat and misunderstanding why. It's not always good to run without a 'stat because you can overcool under the right circumstances, but it has nothing to do with water moving too fast. If an engine runs hot with no thermostat, there's another problem at work

Think about it... Why do people insist that a high volume water pump cools better, yet they say you have to slow it down with a thermostat? (Or they say you have to agitate the water with it - but if a spinning impeller going a couple thousand RPMs won't agitate the water I don't know what will.)

Heat wants to equalize. Circulating the water faster only serves to help that process. It doesn't cause "hot spots" and it doesn't move too quickly through the radiator for it to cool.

Now I'm ready for a chorus of people to call me an idiot and talk about all the people who do this for a living and know better than I do, but I'm right. I promise I am.

 

6 cylinder radiator 302 and 180 themostate and i reach a high of 180
so try it

 

ok im only going off of what ive been taught at school and multiple traing classes ive had. they always say that no t-stat will cause over heating due to the fluid not being in the radiator long enought. i have never removed or ran with out the t-stat but i have had cars that dont have one come in over heating and a t-stat fixed the problem. the high volume pump is not a high pressure pump. it can more coolant but its only going to move as much as the flow rate in the system is capiable of. as for the why running no tstat is bad, i really dont care but i know its bad and wont do it.

 

Oh, I know. Like I said lots of smart people believe it as fact, and tell other people so. It's probably even in print. But lots of smart doctors used to swear leeches cured their patients. That didn't mean they were stupid, just some other older wiser doctor told them it worked and they saw some patients get better, so it had to be true...

But you're right, running without a thermostat is usually a bad idea. You might not get your engine up to its most efficient temp, lubrication might not be as good, compression isn't the same, not to mention you could really be screwed if you did that in a cold climate. Then again it takes a lot longer to heat up without a 'stat, and if you are in a car without enough cooling capacity and you only make short trips, sometimes it's a good band-aid fix for getting around.

And yes, in some cases under very specific circumstances, I could see how running without a thermostat might result in diminished cooling. Water's boiling point increases under pressure. With a restriction in the water neck you might have a pound or two more pressure in the block when the water pump is working against it. Without that restriction, under lower pressure, you might get some localized boiling in certain areas. "Hot spots." When you get boiling you get bubbles, and bubbles are bad for cooling...

But that's a condition that would be remedied with the right amount of antifreeze and/or the right radiator cap. It's really got nothing to do with the thermostat per se, but I think this is why people believe that myth. They may have seen the above set of circumstances come together, then put a thermostat or a restrictor in there and it went away.