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What temperature does your car warm up to?

6K views 29 replies 12 participants last post by  salvy59 
#1 ·
I have noticed that the engine will warm up to approximately 184F and stay there. It is cool here in Houston and I expect that temperature to go up in the hot summer months. :icon_redface:
 
#2 ·
Mine goes to a little over 200 according to the "hidden EVIC".
 
#15 ·
Where 'bouts in the 'hidden' EVIC? I've never stumbled across it (SXT plus/RallyeRedline). I'd assume different models come with more/less info... but if it's in there, I'd like to see it. According to the temp gauge, mine is running a notch plus a little hotter than when new last summer.
 
#3 ·
With the stock thermostat you should hit 203, do you have a Jet 180 installed?
 
#4 ·
Eric,

I do not know what a Jet 180 is, so probably not installed. I quess it's an aftermarket product.

Russell
 
#5 ·
Unless you are talking VERY COLD or VERY HOT your engine should run at your thermostat's rated temp.
 
#6 ·
Well, more like 8-10 degrees warmer than the rated temp. Most folks running the 180 t-stat, including myself, run 188-192 temps.
 
#9 ·
Thank you... learn something new every day! :thanks:
 
#10 · (Edited)
I went for a drive and checked the temps with it idling when I got home, everything up to temp. What I found was...

Lower radiator outlet - ~130F
Water pump inlet from lower radiator hose - ~155F
Water pump housing - ~190F
Upper radiator hose - ~200F

When hitting the track and doing 20-minute lap sessions my coolant temp is steady around 195F, so it seems to be more than sufficient. :)
 
#12 ·
11? 11 what? That doesn't make sense...
 
#19 · (Edited)
I'm confused, I thought (wait at this point I kinda KNOW) the Hemi's ran @ 215-219 normally and hotter in the summer. Our low-speed fans don't come on until 219f, and our high speeds not until 226f. My motor is always 215 (vertical) to 220+ w\ stock T-Stat and fan settings but I easily see 221+ as the high speed has not yet triggered. I can't see anyone here running in constantly in the 200-210f range unless they are in 40f or lower weather on a highway cruising, as the low-speed fan itself only lowers the car to 213, then shuts off until it hits 219 again, so they must they have tuned their fans or have a 180 T-Stat AND tuned the fans. And yeah, if you are getting 184..your engine temp sensor is wrong. Stock will never be that low. T-stat opens @ 203f, low speed 219f, high speed 226f, this is a HOT motor design. It runs far hotter than my fathers 6.2l LS Supercharged CTS-V which stock has 560hp, I can bang through the gears all day (and it is scary fun with that much power) but the engine never seems to go over 220f, but clearly has a better cooling system, even after shutting it off it will cool the motor down, radiator fans will continue running for up to 5 min if driven hard, our motors like to cook after you shut them off after running them hard and shut them off. Anyway I guess it is Dodge's way of beating emissions in a piss poor manor as it robs you of horse power, and honestly, engine life I'd imagine.
 
#21 ·
I can bang through the gears all day (and it is scary fun with that much power) but the engine never seems to go over 220f, but clearly has a better cooling system
I'm not sure what gives you that idea when the setups aren't the same. I run road courses and my coolant temp sticks at 195. Oil temp is a different story.


Also, if you look back a few posts you'll see what the measured temps are coming out of the radiator. Bottomline, the cooling system with these cars is more than adequate, the purpose of the t-stat is to regulate temperature. It does that. I have no doubt that running something even cooler, like a 170, would result in lower runnings temps. The problem is that tends to be TOO cool for the oil under normal driving and as a result the contaminants have a hard time boiling off.


Yes, stock setup the HEMI runs relatively hot. The old 4.0L I6 in the Jeeps used to run hotter. Nothing to do with having a cooling system that's not up to snuff.
 
#22 · (Edited)
the purpose of the t-stat is to regulate temperature.


>>>I always thought the stat regulates flow the fan regulates the temp? the stat only regulates the temp when cold and once the engine temp is up to normal then it only regulates flow, and the fan regulates the temp after the engine is heated up?
 
#23 ·
The t-stat regulates the temp by regulating the flow, the fans are secondary when it comes to cooling. When the car isn't moving the fans are needed to provide airflow across the radiator, otherwise there wouldn't be sufficient heat transfer. The fans also help the A/C work better at low vehicle speeds.


Some vehicles will overheat if the t-stat is removed because there's too much flow and the coolant doesn't spend enough time in the radiator to cool down sufficiently.
 
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#24 · (Edited)
My 2013 392 SRT8 Core runs at 215. I've seen it as high as 230 when running it hard. Dealership mechanic said that's normal. They are set up hot to help with emissions. I've heard when you start cooling them down the catalytic converters can clog because they are not burning off properly. Pretty sure those are not cheep either.


Sent from AutoGuide.com Free App
 
#28 ·
I'm not sure what makes you think there is some magic, exact counter-balance going on with heat transfer from the block to the coolant and coolant to the radiator/air. Perhaps that is what is confusing you, but there is no counter-balance or equilibrium happening where the flow through the radiator pulls exactly the same amount of heat out of the coolant as the coolant absorbs as it travels through the block UNLESS a thermostat is used. Why? Because of time, surface area and the efficiency of heat transfer from one medium to another.

Think about it this way.

You have 3 identical engines all producing the same rated power (not idling), however each one has a different size radiator; One tiny, one "correct size", one huge. None of them have a t-stat installed.

What's going to happen? Do you honestly think that all 3 will operate at the same temperature because there's an exact counterbalance that is exactly the same across all 3? Absolutely not.

When the cooling system and t-stat reach equilibrium and the coolant temperature stabilizes the t-stat is, for a properly-sized cooling system and a vehicle driving under normal conditions, about halfway open. Not fully open. In this state the cooling system still has extra cooling capacity.

Anyway, back to my example, radiators are rated with specific flow ranges, etc. If a removed t-stat results in coolant flow that exceeds the radiators high flow rating then the coolant will not cool off quick enough and it will absorb more heat traveling through the block than it's able to transfer out via the radiator.

So for the engine with the tiny radiator you have a big heat source and a small radiator to dissipate that heat. The engine will overheat.

The engine with the correct radiator should keep up with the heat from the engine since the coolant flow is still within its rating.

The engine with the huge radiator is never going to reach proper operating temperature because the coolant flow will be below the radiator's low flow rating and it's overcooling the coolant.

So, all of our vehicles should come with the properly-sized radiator, right? It's nice to think that, but it's not often the case. Pickups and vehicles with "max tow" packages have additional cooling or larger radiators to increase their cooling capacity since those vehicles need to be able to operate at higher loads for longer periods. Pulling the t-stat (Or t-stats, the DMAX has two and has a way to bypass the radiator when it's not needed for cooling) is likely to result in overcooling because the radiator is meant to be worked harder and have a high flow rate.

Then you have the issue of corrosion and scale build-up inside the radiator. Your t-stat could be operating just fine, the cooling system could still be flowing the same GPH, but the vehicle is overheating. Why? The blockages in the radiator are effectively making it work like a smaller radiator with less capacity and it can't shed heat fast enough even though the coolant is flowing through within the radiator's rating.

There is no downward delta-T that exactly matches the upward delta-T inside the engine without the use of a thermostat and thinking that is only going to lead to the state of confusion that you're in.
 
#29 ·
I think you made my point- when the radiator is OVERsized (as it always is), and you pull out the T-stat so the coolant circulates as fast as the water pump can pump it, the engine will run colder than normal. It won't overheat at all UNLESS a) something is wrong like a clogged radiator, or b) something screwy happens to the coolant flow paths in the block.

In all honesty, I think 99% of the reports of "I pulled the thermostat out and now it overheats!" are due to a) above. Something was WRONG that made the owner pull the T-stat out, and surprise surprise, it still overheats with the Tstat out.

There are some documented engine designs where the coolant flow gets weird when the flow rate gets really high because inertia takes over and stagnation points form, but most of those are 50s and 60s engines. And even then if all else is in good shape, they won't go into runaway overheat, though they'll be unhappy from having some cold cylinders and some hot.

There are also some engines out there where the thermostat is designed to block or restrict the bypass path when it opens all the way (on big-block Chryslers, the brass "plunger" on the back-side of the T-stat pokes down into the cast-in bypass hole when the T-stat opens, for example), so removing those T-stats can definitely cause an issue because now the bypass path isn't ever closed or restricted.

I'll bet you the contents of my wallet that if I went out and took the thermostats out of all my cars and went out and ran them as hard as I could on a hot summer day, the would all 5 run far colder than normal, not a one would overheat. Especially not the Hemi, 4.7, and Pentastar with their CAD-designed cooling systems. But even the two 440s would probably be too cold, if I plugged that bypass I mentioned above at the same time I removed the stat. A removed thermostat isn't that different from a wide-open thermostat, and all car cooling systems are intended to keep working when the T-stat is wide open.
 
#30 · (Edited)
I just learned a lot on how all this works by reading this thread!! I have a 2012 R/T and I always wanted a little Bigger Radiator like a Srt, which is just a little Bigger then what the 5.7 has... I believe a Quart or what ever the measurements are to determine the area of the radiator lol I guess by reading this thread it is not needed?


I can relate to what 440 Magnum is saying only because I was told long ago by a gear head that when the Thermostat is off you create Hot spots in the engine inside the block and can also create blow bye and was told rings can or will be warped because of this... I can remember my uncle back in 1978 took his thermostat out on his Pontiac during the summer months, well few years later the car was burning oil lol

I always remembered my uncle situations burning oil, this is the reason why I happen to ask this gear head of what could have been the problem.... Great thread how the coolant system works... Thanks Guys!!!
 
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