are there lower temperature thermostats for our cars?

Looked around but all i see is stock temps nothing with lower
anyone have insight?

 

Even if they were available , running an engine below design spec carries no benefit.

 

You'd have to also find a temp sensor to match it, otherwise you'll get an 'under temperature' code thrown (that's what I got when my thermostat was stuck open).

 

im ony looking for a 10degree lower, Do not think it will effect the under temperature warning light

 

What do you hope to gain?

 

Other then the design parameters are developed to run at a certain temperature why would you want to effect that. What temperature are you running at now and what would you like to see. My 2012 XKR runs at 195* on the open road and will spike to 205* in traffic on a 90* day. Considering that 10 or 20 degrees higher is no problem I don't think there is any advantage going to a lower temp.

 

The emissions and other systems are designed to function at 85oC to 90oC or certain DTCs may be set triggering the MIL.

 

Aren't you more concerned with the correct temperature rather than 10 degrees wrong?

 

You all do realize that if a thermostat opens at a lower temperature that has zero affect on the running temperature of the engine right? All it means is that at a certain temp the thermostat opens which then allows the coolant to flow throughout the radiator versus being cut off and flow only through the engine block until it opens. This makes a bit of difference in cooler temps when you may want it to open a stay closed a tiny bit longer in order to get the engine to operating temp sooner but again once the thermostat is opened it makes not difference if it opens at 195 or 205 the engine will still run at the same temperature. In the end I have no idea why you would want to monkey with the original design or what your end-goal is hoping to accomplish

 

I disagree as the design of the thermostat is to maintain a certain temperature . A 175* will maintain 175 +/- while a 195* does the same. A 175 should not run at 195 unless there is a problem with the system. The cooling system is designed around the heat range required for the efficiency of the engine. The thermostat modulates the flow of coolant to maintain it's design setting. Because it opens at a lower temperature it should not allow the engine to overheat or exceed the set range. The sweetspot for most engines is around 200*F.

 

I disagree as the design of the thermostat is to maintain a certain temperature . A 175* will maintain 175 +/- while a 195* does the same. Incorrect. A thermostat opens within @3 mins of your engine running. Once open it stays open. It is only a gate, or valve, that allows the coolant to circulate through the engine block until such time it reaches the temperature where it opens (be it 175, 190, etc) then essentially it does nothing except let the coolant through the entire system to be then cooled by the radiator. A 175 should not run at 195 unless there is a problem with the system. Sort of, if the engine exceeds a desired temp then the fans kick in so as not to hopefully become overheated. Again that has nothing at all to do with the thermostat unless it gets stuck in the closed position whereas it is not letting the coolant flow through the radiator. Again it does nothing once opened and even in extreme cases of cold climate it is open after only a few minutes of running. The cooling system is designed around the heat range required for the efficiency of the engine. The thermostat modulates the flow of coolant to maintain it's design setting. Because it opens at a lower temperature it should not allow the engine to overheat or exceed the set range. Partially correct. The thermostat is only a function of letting the engine warm up more or less quickly it does not regulate what temp it runs at unless it is faulty or blocked then you're looking at failure of the coolant to enter the radiator. It is nothing but a gate once opened it does not close while the engine is running, it does not regulate or monitor anything that is more of a function of the fans in situations where heat is about to be exceeded.What the design and desired operating temp of an engine is has everything to do with airflow, and even oil cooling and nothing to do with thermostat. It is only a minor switch/gate/or valve. The sweetspot for most engines is around 200*F. Correct on that. If you were to remove the thermostat it would have two affects - first it would take longer for your car to reach desired operating temperature as the coolant would be traveling through the radiator instead of solely the block. Secondly is the fact that is somewhat slows the coolant instead of letting it "freeflow" it may cause overheating as the coolant would not spend enough time in the radiator to actually cool the coolant but if you could slow it down the actual effect of doing so would be zero difference. The thermostat does not regulate the engine temp once it has reached operating temp not does choosing a higher or lower temp affect what temp your engine runs at only how quickly or slowly it exceeds the temp the thermostat is designed to open at (a 175d thermostat will open at that temp then continue to stay open regardless of how much higher the temps get... as you stated the avg desired temp is @195 so once the engine has exceeded 175 the thermostat opens, allowing coolant to enter the radiator, and therefore it is doing nothing). In cold weather climates some people in older cars would sometimes prefer a higher opening thermostat as it would allow their cars to warm up quicker so the coolant would only circulate in the engine block longer so to get to operating temperature sooner, that is rarely the case with newer cars in the last many years... also in some cases when racing but with standard road cars people VERY rarely mess with the design as there is little to no gain.

Think of it like our light sensors, when it senses light has reached a certain level of darkness our automatic lights turn on, once on our headlights project, it makes no difference how much darker it gets that sensor still illuminates our lights, they get no brighter as it darkens more. The difference is that eventually if we were to drive long enough it would then become brighter and that sensor wold then turn off our lights whereas as long as you're driving your car the engine does not reduce temperature, even while driving in extreme cold temps, so once opened the thermostat does not "modulate" or monitor in any way and won't until such time as the engine is turned off and the coolant in the block has cooled below the rating of the thermostat that the tiny bi-thermal piece in it closes. If you've ever taken a close look at a thermostat all it is is a tiny bellow looking thing and in the center is a thing resembling a 1/8" woofer, nothing more, it is a bi-metallic piece where two pieces of metal expand at different rates either opening or closing a tiny bit

 

No, thermostats constantly open and close, at least partially, to try to maintain the target temperature. The bi-metallic contractions and expansions will not magically "STAY" once they get to a point. That would be what you'd call a "STUCK THERMOSTAT".
If it stayed open, then the engine temperature would drop to the maximum efficiency of the cooling system, which COULD be quite low, especially in cold weather. Stuck closed, and you'd be skrood.

 

Thermostats can be stuck in open or closed positions, stuck open means it takes a longer time for the engine to reach desired temperature (which means metals are not at the most desired temps for maximum efficiency), stuck closed is fine... for a short time then no bueno. They do not modulate as the coolant even with great airflow or in low OAT's the engine produces temps well above the 175'ish temp so the thermostat stays open relying on the radiator, oil, and airflow to cool it.

OAT's mean little to modern ICE engines with the exception of getting to desired operating temps, that's why for the most part whether you're driving in 0 degree OAT or 105 the engine still runs within a very narrow band of temps and we don't change our thermostats however it does take longer for them to reach that temp. In each of those instances the thermostat i still fully open, all the time, after only a few minutes of running. The same is said for air cooled car engines (VW's, older Porsches, etc) and most aircraft engines as they have neither coolant nor thermostats however they run in a narrow operating temperature regardless of OAT (outside air temperatures)

Again once the coolant has exceeded the designed opening temp (be it 175 or 190 degrees) it opens, once it cools to below that it closes (unless it is "stuck"), and it is either opened or closed using a super simple design, but it won't close again unless you turn off the engine letting the coolant reduce temp

 

Wrong, wrong, wrong. I suggest a Google search for you. Or maybe a beginner's course in physics.
If a thermostat was fully OPEN and never closed not even a tiny bit, then the vehicle's cooling system would be the "modulator" for the system. If it was an EXTREMELY EFFICIENT cooling system, then the returning coolant would be at ambient air temperature when it reentered the engine. If that ambient temp was -40f, then you'd have one heck of a cracked block. The engine would also heat to normal operating temps ONCE, then cool back down to whatever the cooling factor of the radiator was.
Regardless, what I will paraphrase your diatribe to mean......... Once a thermostat opens it will STAY OPEN, regardless of how hot/cold the coolant is. Therefore, even if the engine is OFF and the ambient temperature is -400k, the thermostat will STILL never close. Never mind the metallurgy behind cold contracts and heat expands, and that some heat will expand somewhat and some cold contracts somewhat. PHYSICS BE DAMNED!!!!!!!!!!!
That makes zero sense.

 

I guess they must have redesigned the thermostat . It used to be a regulating valve and not an open/close switch. Maybe I'm thinking old school where it would cycle to maintain a designed temperature. Learn something new every day.

 

jagtoes, thanks for corroborating my statements. Can't stop physics.

 

Wrong, wrong, wrong. I suggest a Google search for you. Or maybe a beginner's course in physics. I did exceptional in my college physics courses thank you for asking
If a thermostat was fully OPEN and never closed not even a tiny bit, then the vehicle's cooling system would be the "modulator" for the system. If it was an EXTREMELY EFFICIENT cooling system, then the returning coolant would be at ambient air temperature when it reentered the engine. That would be ideal in concept but the base level idea is correct thus far

If that ambient temp was -40f, then you'd have one heck of a cracked block. That is called "shock-cooling which is a real issue when dealing with air-cooled aircraft engines where you shut down the engine too quickly however this concept is where your theory is in error with a water-cooled ICE. The radiator is of course unable to fully dissapate all the heat created by the engine only cooled somewhat and only a small amount at a time

The engine would also heat to normal operating temps ONCE, then cool back down to whatever the cooling factor of the radiator was. You're thinking in "absolutes", as though the engine is HOT and the radiator brings the coolant temp to OAT but this is only happening in small amounts where the engine heats the coolant not in an instant nor is it cooled in an instant but both are working in tandem against each other with the end goal of maintaining a certain desired temp
Regardless, what I will paraphrase your diatribe to mean......... Once a thermostat opens it will STAY OPEN, regardless of how hot/cold the coolant is. Incorrect. The thermostat will stay closed until it reaches the temp it is designed for (be it 175 or 190, etc) at which point it opens letting the heated coolant to enter the radiator with hopes of it cooling, once the coolant has lowered its temp to whatever the thermostat is designed to close at it will then close only allowing the coolant to circulate around the bloack therefore NOT entering the radiator... and this closing of it only happens after the engine is turned off. Make sense? It is a simple switch so to speak

Therefore, even if the engine is OFF and the ambient temperature is -400k, the thermostat will STILL never close. Exactly the opposite, if it is -400f it would never open, nor at 105, or 150, not until it reaches the designed opening temperature.

Never mind the metallurgy behind cold contracts and heat expands, and that some heat will expand somewhat and some cold contracts somewhat. PHYSICS BE DAMNED!!!!!!!!!!!
That makes zero sense.

The hope of a thermostat is so that an engine will reach its most efficient operating temp as soon as possible, and that is a design of the metallurgy of the bearings, pistons, rings, etc. The sooner it can get to that temp the better it is, the less wear, better mpg, more power, etc and the thermostat allows the engine to get UP TO that temp sooner, it is not there for cooling purposes with the exception that on most cases if you remove it the ill effect is that it will not only take longer for it to reach that desired temp but often the coolant is totally unrestricted now so flows too quickly through the cooling system not giving the radiator enough time to cool the coolant thus it could cause overheating

 

The guys are correct in stating that a thermostat is not an off/on device like a light switch. It's much closer to a device that's being governed to operate at a constant set point whether that be speed, load, altitude or in this case temperature. The thermostat is in a constant state of adjustment attempting to achieve a balanced state.

If a car has enough cooling system capacity, the engine can be made to run at a lower temperature with a different thermostat.

But the question still remains as to why the OP wants to do that.

 

As said the notion of changing I've only heard of for extreme racing purposes or in old cars in extreme weather conditions... it sounds like only a detriment in modern cars with electronic engine management. Have absolutely no idea why someone would have any desire to monkey with it. It's such a small inconsequential item to mess it and is hell if it gets messed up, no clue as to what the hoped benefit is

 

We agree to disagree and now have a better understanding of your automotive knowledge.