ECT/EOT/TFT while towing
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Now that's funny.It's just a personal thing, I had a heavy background in physics and engineering and to hear/see "Delta" used in such a way is like nails on a chalkboard.
Josh
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Have to use search somehow. I know my own temp spread improved 2 degrees in 2012 from the stock t-stat to the Motorcraft.
My current Mishimoto seems to be about the same as before.
Speaking of Mishimoto, I believe there are a couple examples in that thread where the temp difference lessened with the 200 t-stat
Josh
My current Mishimoto seems to be about the same as before.
Speaking of Mishimoto, I believe there are a couple examples in that thread where the temp difference lessened with the 200 t-stat
Josh
Not doubting it happened for some folks, just would like to know the mechanism because if a temperature differential is reduced, then it pretty much seems to me that the flow through the cooler had to change (increase) since the heat exchange area of the oil cooler is constant. Not sure how that would happen, but I can accept that it does for some situations.
The ECT is the hot water temp and the EOT is the cold oil temp. So, if you raise the overall water temp (and keep the coolant flow the same), then I just can't see anything happening other than the oil temp going up also - by about the same amount.
Q=U*A*delta T (for the engineering background). You simply can't remove more heat (actually enthalpy) from the oil (reduce it's outlet temp, or even keep it the same) with warmer inlet water unless the flow changes.
If there are flaws in that thinking, I certainly would not mind hearing what they are and how it would support a reduction in the ECT/EOT differential.
Thoughts?
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Thanks. Money-Pit PM'd me and referred me to that thread - I hadn't kept up with it.
Not doubting it happened for some folks, just would like to know the mechanism because if a temperature differential is reduced, then it pretty much seems to me that the flow through the cooler had to change (increase) since the heat exchange area of the oil cooler is constant. Not sure how that would happen, but I can accept that it does for some situations.
The ECT is the hot water temp and the EOT is the cold oil temp. So, if you raise the overall water temp (and keep the coolant flow the same), then I just can't see anything happening other than the oil temp going up also - by about the same amount.
Q=U*A*delta T (for the engineering background). You simply can't remove more heat (actually enthalpy) from the oil (reduce it's outlet temp, or even keep it the same) with warmer inlet water unless the flow changes.
If there are flaws in that thinking, I certainly would not mind hearing what they are and how it would support a reduction in the ECT/EOT differential.
Thoughts?
Not doubting it happened for some folks, just would like to know the mechanism because if a temperature differential is reduced, then it pretty much seems to me that the flow through the cooler had to change (increase) since the heat exchange area of the oil cooler is constant. Not sure how that would happen, but I can accept that it does for some situations.
The ECT is the hot water temp and the EOT is the cold oil temp. So, if you raise the overall water temp (and keep the coolant flow the same), then I just can't see anything happening other than the oil temp going up also - by about the same amount.
Q=U*A*delta T (for the engineering background). You simply can't remove more heat (actually enthalpy) from the oil (reduce it's outlet temp, or even keep it the same) with warmer inlet water unless the flow changes.
If there are flaws in that thinking, I certainly would not mind hearing what they are and how it would support a reduction in the ECT/EOT differential.
Thoughts?
See a similar concept with the old Ford FE engines (360, 390, 427, 428 etc). Many think they can run 160 degree t-stats versus the stock 180 and the engine will run cooler.
Nope, what actually happens is the engine ends up running hotter since the t-stat is open further causing the coolant to flow faster thru the radiator. Not as much heat transfer and the end result is coolant temps topping 210 or more.
So, what does a person do? Install a 195 t-stat and it stays at 195. T-stat remains barely open, reducing flow and allowing the radiator to do it's job.
That is one example.
Not much different than the Sinister oil cooler with the bigger internal passages. Too much flow and not enough saturation time which equals hotter EOT.
Josh
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I understand what you are saying with regard to water temps (engine temps) and properly sized thermostats, but for oil to be cooler (reduced differential), the water flow in the oil cooler has to increase. I guess I need to chew on it a little more.
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Josh
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This escalated to a point I didn't think it would go, but its great. I wish it wasn't so cold out. I would change the t-stat and see what happens. But then that probably still wouldn't prove it one way or the other.
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I'm leaning towards revising my theory on how a hotter or at least a proper t-stat could close the temp gap on ECT/EOT.
Several PM exchanges with Bismic, followed with links to others having the exact discussion has led me to believe the hotter coolant provides more heat "capacity" allowing the EOT to cool off more. Extremely basic definition of my understanding.
I previously thought the hotter t-stat slowed the coolant down, but upon more reading wouldn't really work in an engine cooling system. Looks like, if anything, the slower coolant would increase the temp spread, not reduce it.
Links as follows:
https://www.physicsforums.com/thread...ansfer.198975/
I clued in on Post #19 in this link:
coolant flow question - The Garage Journal Board
Josh
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As far as the flow through the cooler from how mine acted before the Mishimoto tstat and after I would say this is the case. My eot is alot more "responsive" with the Mishimoto tstat. Before it would be very slow to move down when the ect went down and my splits were up to 10 ° or more. Now it's normal at 5° at 65 and steady for what it's worth.
2006 F350 4X4
2006 F350 4X4
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From: 'Pitlock, Maine
I'm one of them, when my tstat was at or near 180-182 my deltas were 10-11......new tsat and ECT was 188-190 EOT was was/is 6-7* warmer. I can't explain it but I know it to be true.
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Either way, my old rig is 12 years old and has 129k so its getting a new t-stat. I will make a point to do a run the day or so before and record the results. Then do a post run and post those results. But first, its getting the rearend leak fixed Monday. Its one thing at a time. I put on new front tires last week and moved the fronts to the outside rear. That was almost a $500 bill. If I don't end up doing the oil cooler again I would like to get the engine oil leak fixed at some point but that's a whole different story.
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Either way, my old rig is 12 years old and has 129k so its getting a new t-stat. I will make a point to do a run the day or so before and record the results. Then do a post run and post those results. But first, its getting the rearend leak fixed Monday. Its one thing at a time. I put on new front tires last week and moved the fronts to the outside rear. That was almost a $500 bill. If I don't end up doing the oil cooler again I would like to get the engine oil leak fixed at some point but that's a whole different story.
2006 F350 4X4
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That's what we do here!
I'm leaning towards revising my theory on how a hotter or at least a proper t-stat could close the temp gap on ECT/EOT.
Several PM exchanges with Bismic, followed with links to others having the exact discussion has led me to believe the hotter coolant provides more heat "capacity" allowing the EOT to cool off more. Extremely basic definition of my understanding.
I previously thought the hotter t-stat slowed the coolant down, but upon more reading wouldn't really work in an engine cooling system. Looks like, if anything, the slower coolant would increase the temp spread, not reduce it.
Links as follows:
https://www.physicsforums.com/thread...ansfer.198975/
I clued in on Post #19 in this link:
coolant flow question - The Garage Journal Board
Josh
I'm leaning towards revising my theory on how a hotter or at least a proper t-stat could close the temp gap on ECT/EOT.
Several PM exchanges with Bismic, followed with links to others having the exact discussion has led me to believe the hotter coolant provides more heat "capacity" allowing the EOT to cool off more. Extremely basic definition of my understanding.
I previously thought the hotter t-stat slowed the coolant down, but upon more reading wouldn't really work in an engine cooling system. Looks like, if anything, the slower coolant would increase the temp spread, not reduce it.
Links as follows:
https://www.physicsforums.com/thread...ansfer.198975/
I clued in on Post #19 in this link:
coolant flow question - The Garage Journal Board
Josh
Even if a hotter running T-stat was able to lower the temp differential between ECT and EOT it is not really solving the initial problem. This is only masking the fact that the cooler may be working less efficient than intended. In my mind raising the coolant temp to get a lower differential is only masking the issue at hand.
Since the Ford spec is a 15 degree difference, unofficially may be 7 or 8, based on a 192 degree T-stat then maybe we need a new set of numbers for a 200 degree T-stat. If the efficiency changes with the ECT then we can not use the differential for 192 at 200. If the effiency changes then the measurement of how efficient it is must change as well.
My logic may be completely off base but it seems logical to me, LOL.
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Thanks. Money-Pit PM'd me and referred me to that thread - I hadn't kept up with it.
Not doubting it happened for some folks, just would like to know the mechanism because if a temperature differential is reduced, then it pretty much seems to me that the flow through the cooler had to change (increase) since the heat exchange area of the oil cooler is constant. Not sure how that would happen, but I can accept that it does for some situations.
The ECT is the hot water temp and the EOT is the cold oil temp. So, if you raise the overall water temp (and keep the coolant flow the same), then I just can't see anything happening other than the oil temp going up also - by about the same amount.
Q=U*A*delta T (for the engineering background). You simply can't remove more heat (actually enthalpy) from the oil (reduce it's outlet temp, or even keep it the same) with warmer inlet water unless the flow changes.
If there are flaws in that thinking, I certainly would not mind hearing what they are and how it would support a reduction in the ECT/EOT differential.
Thoughts?
Not doubting it happened for some folks, just would like to know the mechanism because if a temperature differential is reduced, then it pretty much seems to me that the flow through the cooler had to change (increase) since the heat exchange area of the oil cooler is constant. Not sure how that would happen, but I can accept that it does for some situations.
The ECT is the hot water temp and the EOT is the cold oil temp. So, if you raise the overall water temp (and keep the coolant flow the same), then I just can't see anything happening other than the oil temp going up also - by about the same amount.
Q=U*A*delta T (for the engineering background). You simply can't remove more heat (actually enthalpy) from the oil (reduce it's outlet temp, or even keep it the same) with warmer inlet water unless the flow changes.
If there are flaws in that thinking, I certainly would not mind hearing what they are and how it would support a reduction in the ECT/EOT differential.
Thoughts?
There is also a difference in energy transfer rates as temperature changes between the mediums (individually and maybe more significantly compared to each other) and the overall temp of the super system. I tried to research this a bit to try and understand the significance of the idea but got bogged down by Gibbs equation and some other concepts I don't know about and now my head hurts.
I would also add the coolant isn't removing more heat from the oil. The oil is returning to the cooler at the same temp (or maybe higher due to the increase in engine temp) and is exiting at a higher temp, the oil temp increase is less than the coolant temp increase which would mean it's somehow more effencient right?
If the 220° stat install was the only change, no fresh coolant or flush and no oil change, the only variables that are different are the temps and flow rate.