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my perfect cooling system

If the coolant flow would be too fast the radiator outlet temperature would be hotter, if you would be able to monitor that temperature you could see if it makes a difference between standard flow and high flow.
But if this works it means the radiator has sufficient efficiency.

Thing to remember is that not all coolant passes through the radiator once coming from the engine, a part of the hot water is returned and mixed with the cooled water return from the radiator and goes back into the cooling pump suction.
That mixed result inlet temperature, and the heat absorbed from the engine make the outlet temperature that you see on the temp gauge, and that same temperature is what your thermostat is trying to control.
If the heat input from the engine increases due to more load, the outlet water temperature is higher and will open the thermostat more so it will send more coolant to the radiator and less back to the engine pump inlet.
That's why the flow through the radiator needs to result in the right temperature difference (ΔT), too fast of a flow will not reach this and wil result in a too high water inlet temperature, which results in a higher outlet temperature.

A 180* thermostat will start to open @ 180*, but might only be fully open at 195*.
So when seeing 190* on the gauge after a strip run is normal as the heat absorbed from the engine is suddenly very high and the thermostat will be able to bring that down again after several minutes when the load is gone.
When standing in traffic at hot days and seeing +190* is therefore actually showing your cooling system is not able to provide sufficient cooling.
Of course is the air flow low, an a/c condensor is another air flow obstruction and causes an increased air temperature to pass the radiator so these things do increase the temperature to maybe 186-188* in a healthy system.
In the above case a temperature of 195* or higher proves the thermostat is fully open and is no longer able to control the temperature as it is sending the maximum amount of water to the radiator for cooling.

Turned out a little long, but just something to read for the ones who want to know i guess. :D


well i dont think that will be a problem with my system . but thanks
 
If the coolant flow would be too fast the radiator outlet temperature would be hotter, if you would be able to monitor that temperature you could see if it makes a difference between standard flow and high flow.
But if this works it means the radiator has sufficient efficiency.

Thing to remember is that not all coolant passes through the radiator once coming from the engine, a part of the hot water is returned and mixed with the cooled water return from the radiator and goes back into the cooling pump suction.
That mixed result inlet temperature, and the heat absorbed from the engine make the outlet temperature that you see on the temp gauge, and that same temperature is what your thermostat is trying to control.
If the heat input from the engine increases due to more load, the outlet water temperature is higher and will open the thermostat more so it will send more coolant to the radiator and less back to the engine pump inlet.
That's why the flow through the radiator needs to result in the right temperature difference (ΔT), too fast of a flow will not reach this and wil result in a too high water inlet temperature, which results in a higher outlet temperature.

A 180* thermostat will start to open @ 180*, but might only be fully open at 195*.
So when seeing 190* on the gauge after a strip run is normal as the heat absorbed from the engine is suddenly very high and the thermostat will be able to bring that down again after several minutes when the load is gone.
When standing in traffic at hot days and seeing +190* is therefore actually showing your cooling system is not able to provide sufficient cooling.
Of course is the air flow low, an a/c condensor is another air flow obstruction and causes an increased air temperature to pass the radiator so these things do increase the temperature to maybe 186-188* in a healthy system.
In the above case a temperature of 195* or higher proves the thermostat is fully open and is no longer able to control the temperature as it is sending the maximum amount of water to the radiator for cooling.

Turned out a little long, but just something to read for the ones who want to know i guess. :D

Based on some of your suppositions, it sounds like you have a working knowledge of thermodynamics. However, once the thermostat is open, no mater what the calibrated opening temperature is, I believe the issue comes down to the velocity and volume of the heat transfer fluid, both the entering and exiting temperature of the heat source and the entering and exiting temperature of the heat exchanger as well as the air temperature entering and exiting the radiator. The blend temperature of the recirculated heat transfer fluid in the engine, when the thermostat is partially closed/open, is an unknown factor, unless the recirculated volume and temperature is known b4 the blended delta T influence is known or can be calculated. If the pressure loss across the thermostat is known or area detetmined, then the blend volume could be calculated to detetmine the resultant heat gain/loss of the heat source could be factored in the overall heat load the radiator must dissipate. Its not a straight forward analysis due to fact that the fluid flow volumes are constantly changing, due to engine's constant RPM changes and air flow volumes across the radiator. Perhaps, if the average BTU heat load generated, plus a 15% safety factor, to allow for ambient temperature excursions, were known, a better analysis could be presented or possibility determined iteratively, using several different data points and averaged. Just my opinion of course.
BOB RENTON
 
^^^ While your trying to "Dazzle 'em with foot work" the problem is already getting knocked out.
 
Based on some of your suppositions, it sounds like you have a working knowledge of thermodynamics. However, once the thermostat is open, no mater what the calibrated opening temperature is, I believe the issue comes down to the velocity and volume of the heat transfer fluid, both the entering and exiting temperature of the heat source and the entering and exiting temperature of the heat exchanger as well as the air temperature entering and exiting the radiator. The blend temperature of the recirculated heat transfer fluid in the engine, when the thermostat is partially closed/open, is an unknown factor, unless the recirculated volume and temperature is known b4 the blended delta T influence is known or can be calculated. If the pressure loss across the thermostat is known or area detetmined, then the blend volume could be calculated to detetmine the resultant heat gain/loss of the heat source could be factored in the overall heat load the radiator must dissipate. Its not a straight forward analysis due to fact that the fluid flow volumes are constantly changing, due to engine's constant RPM changes and air flow volumes across the radiator. Perhaps, if the average BTU heat load generated, plus a 15% safety factor, to allow for ambient temperature excursions, were known, a better analysis could be presented or possibility determined iteratively, using several different data points and averaged. Just my opinion of course.
BOB RENTON

Yes there are more factors as flow, Delta T, pressure loss and turbulence involved in thermodynamics as you mention, but that becomes a very long and technical story.
The blend temperature entering the engine can be monitored if you would be able to install a temperature sensor in the pump outlet. (probably this would ideally be around 160-165*)
This temperature is quite critical, obviously should not be too high, but for sure not too low either as a too low temperature is not good for the combustion process.
The thermostat you purchased will tell you a certain opening temperature on the package, say 180* F, the other temperature which normally is not mentioned is the fully open temperature, say 195*.
The 180* indicates the temperature it will start to open and continue to try to maintain that temperature.
If the coolant does start to exceed 180*, it will open more and direct more coolant to the radiator.
In this case, at 195* the thermostat is fully open and feeding maximum amount of coolant through the radiator and the cooling system will no longer be able to keep it cool.
The pump displacement in gallon/min changes only slightly when the thermostat functions through its range due to different back pressures, just more coolant is directed through the radiator.

The main simple things to keep in mind is that the cooling system must be able to have the capacity of dissipating more heat (say Kw as a value) than the engine can produce, which is at maximum load.
One can assume that that happens when the car is doing high speeds, therefore has a high air flow to deal with it.
That same cooling system must be able to keep the engine cool as well in a high ambient temperature with a low air flow and an engine that just ramped down from high way speed and being stuck in traffic.
2 very different situations that require a very versatile cooling system.
To keep things simple is the fact that the original cooling system works very well as it is "calculated" for its application, and will be able to cope with some additional horsepower from cams and headers.
Realize why these cars were equipped with a 26" radiator if a track pack or any other "race" axle or towing package was ticked in the option list, due to higher rpm at lower speeds and/or higher loads (towing) at lower speeds.
 
Yes there are more factors as flow, Delta T, pressure loss and turbulence involved in thermodynamics as you mention, but that becomes a very long and technical story.
The blend temperature entering the engine can be monitored if you would be able to install a temperature sensor in the pump outlet. (probably this would ideally be around 160-165*)
This temperature is quite critical, obviously should not be too high, but for sure not too low either as a too low temperature is not good for the combustion process.
The thermostat you purchased will tell you a certain opening temperature on the package, say 180* F, the other temperature which normally is not mentioned is the fully open temperature, say 195*.
The 180* indicates the temperature it will start to open and continue to try to maintain that temperature.
If the coolant does start to exceed 180*, it will open more and direct more coolant to the radiator.
In this case, at 195* the thermostat is fully open and feeding maximum amount of coolant through the radiator and the cooling system will no longer be able to keep it cool.
The pump displacement in gallon/min changes only slightly when the thermostat functions through its range due to different back pressures, just more coolant is directed through the radiator.

The main simple things to keep in mind is that the cooling system must be able to have the capacity of dissipating more heat (say Kw as a value) than the engine can produce, which is at maximum load.
One can assume that that happens when the car is doing high speeds, therefore has a high air flow to deal with it.
That same cooling system must be able to keep the engine cool as well in a high ambient temperature with a low air flow and an engine that just ramped down from high way speed and being stuck in traffic.
2 very different situations that require a very versatile cooling system.
To keep things simple is the fact that the original cooling system works very well as it is "calculated" for its application, and will be able to cope with some additional horsepower from cams and headers.
Realize why these cars were equipped with a 26" radiator if a track pack or any other "race" axle or towing package was ticked in the option list, due to higher rpm at lower speeds and/or higher loads (towing) at lower speeds.

I appreciate your comments and analysis. YES...i realize the design parameters involved in making the cooling system function efficiently in an average set of conditions. I use to design and specify heat exchanger systems, both gas to gas, gas to liquid, and liquid to liquid types. Each application is specific to the intended service. Automotive cooling systems are no exception. YES....it would be nice if the total heat loads were known, either in BTU/Hr, Kw, or kiloCalories/unit of time or some other quantifiable unit. Sometimes the use of canned computer programs are helpful as the "old method" of using simultaneous equations in 3 or 4 unknowns is very cumbersome and error prone.
BOB RENTON
 
Chrysler already did the math in those years, therefore i think to stick to it as it is.
That would be a safe way of keeping things good and simple.
The guys here racing do need modifications accordingly but for a street/strip machine i believe you do not require too much fancy stuff.

I do appreciate the OP sharing his setup, which reminds me to do something about my poorly installed shroud with a gap on the top and bottom. ('69 shroud vs '70+ radiator)
These adhesive foam strips or plastic strips seems to be something that will help me out as well and gain some more cooling efficiency.
 
boy oh boy did not intend to make trouble . you gents are very smart . remember i wanted to keep this on a simple level for the members that dont understand all the technical engineering that goes into the math and time it would take to learn that . some of us have a.d.d or dyslexia so it can be hard to wrap your head around your knowledge .
 
ok so last night i was filling the cooling system and looking for leak's and as i look i find a leak look like the water pump housing then i found the t-stat housing was the leak . and it was my fault the bolt hole in the gasket was to long for the new t-stat housing for the pro-flow you can see that the gasket doesn't cover all of where the t-stat lip sits in the housing. i did not look close a year ago when i did all the cam shaft and cylinder heads work . so look close at what you are doing the little things will bite your ***.
.
t stat 2.jpg
 
Interesting...
A "stock" type thermostat, the kind with a sort of flange around it, sits directly down in the recess
in the top of the water pump housing usually - with the gasket on top of it.
The gasket "sandwiches" the t-stat between it and the housing; the gasket seals against the neck flange
and the housing flange.
Does the type you're using install differently?
 
Interesting...
A "stock" type thermostat, the kind with a sort of flange around it, sits directly down in the recess
in the top of the water pump housing usually - with the gasket on top of it.
The gasket "sandwiches" the t-stat between it and the housing; the gasket seals against the neck flange
and the housing flange.
Does the type you're using install differently?


this is not a stock t-stat housing it is a 90 deg elbow for the pro-flow fuel injection system the housing has the recess for the t-stat the mopar aluminum water pump housing dose not have a grove for the t-stat it is flat.
 
Chrysler already did the math in those years, therefore i think to stick to it as it is.
That would be a safe way of keeping things good and simple.
The guys here racing do need modifications accordingly but for a street/strip machine i believe you do not require too much fancy stuff.

I do appreciate the OP sharing his setup, which reminds me to do something about my poorly installed shroud with a gap on the top and bottom. ('69 shroud vs '70+ radiator)
These adhesive foam strips or plastic strips seems to be something that will help me out as well and gain some more cooling efficiency.
You know, I've always felt the same way - that is, until I ran across certain applications that made me scratch
my head.
Perfect example is my current GTX "Fred" - he came originally with a 22" radiator to cool the 440!
Not real sure that setup ever worked optimally....
And now that our engines have typically been through some rebuilds and such (and thinner cylinder walls caused
by overbores), sometimes they generate a LOT more heat than they ever did stock - which I also have with
this car.
I'd always heard some 440's run hot as heck. Now I have one that does so...
22" radiator is long gone, replaced by a 26" Griffin "exact fit" aluminum 2-core (1.25" tubes!!) that's 3" thick.
Quite the difference, but even with it and a factory shroud and fixed 18" fan, at idle in traffic, the car
gets quite warm. Once underway, it cools off quite nicely.
 
you can see the t-stat housing under the throttle body

pro-4-2.jpg
 
That's a tight fit there below the TB.
I remember i had alu flange i wanted to install between the block and hose tail to provide space for temperature sensors for EFI.
When i opened the thermostat housing and noticed the size difference on the flange i decided i will find another way to get the sensor installed.
Looked the same as you showed in the picture, supposed to be for a 440 though.
 
That's a tight fit there below the TB.
I remember i had alu flange i wanted to install between the block and hose tail to provide space for temperature sensors for EFI.
When i opened the thermostat housing and noticed the size difference on the flange i decided i will find another way to get the sensor installed.
Looked the same as you showed in the picture, supposed to be for a 440 though.


not as tight as it looks but i can remove once i remove the air intake and it comes out over the coolant temp sensor for the fuel inj, system. reinstalled after i made my own gasket as no part suppliers in Orlando did not have one very small amount of silicone sealer top and bottem and no leak now.
 
ok so over the holiday i had time off so time to start the car for the first time in 10 years . started up ran a little ruff with the new pro=flow fuel inj, system and after setting timing and checking thing the cooling fan controller was bad and the fan would work then not turn off . i got mile on the set up . called derale went thru a few test and they said they would warrant it. so im waiting on the replacement.
 
UPDATE so this weekend i got the warranty derale duel fan controller and installed it did the same did not come on at 180 to 190 shut down car adjusted the on temp 1 fan came on then start car and the fan 1 came on at 200 both came on then fan 2 shut off and the #1 fan stayed on and the #2 fan never came back on so a failed controller . i will now order the auto cool guy p.w.m fan controller and update after i install it.
 
ok so after 2 part failures i have ordered the AUTO COOL GUY'S p w m fan controller . i like the design of it as it use's the ground to turn the fans on , they are power all the time and e-z adjustment of the % of fan you need base on the outlet temp just bush a button to change the temp the fan starts at and the speed i.e % of the fan.
 
So here’s a video of the car with the new cooling fan controller and it works really really good. Working all the bugs out and it looks like the alternator won’t keep up I was hoping that they would but it looks like I will have to upgrade to 130 amp alternator and run a larger wire for that alternator. Someone here said they didn’t like the intellitronix Dash it didn’t work the miles on the odometer would go up with the RPM wiring is very fussy and all cars and you must make sure it’s right so shielding is something that when you’re running tack wires speed generator impulse signals they cannot be in irrupt it or cross talk between them so shielding is most important and I believe that’s why my dash works so good. Just a few more things for tires played it and it’ll be on the road we’re getting there a little at a time
 
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