Your cooling mods and results?

kcbrown

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Just to stir things up a bit...
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Seems that the test data suggests, according to Kendall at Cooltech, that running an air to oil cooler in series with the Boss water to oil cooler is the most effective option: http://forums.themustangsource.com/...-oil-cooler-now-available-504360/#post6233761


If the Boss oil "cooler" is actually acting in a detrimental fashion here, then that should show up in Track Package GTs overheating in conditions where GTs that lack the Track Package don't. Do we actually see this?


ETA: Also, Ford changed the hood design for 2013, and now includes vents. Is there any data showing the frequency of overheating issues as a function of year? It would be interesting to see if the 2013 and later cars are faring better...
 
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Pentalab

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Why are you still arguing?

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2+2=4.... not 8. Measure the cross sectional surface area of all 22 open honeycombs....then compare it to the entire cross sectional area of the entire grille.... including foglamps, pony, and the tapered portions outboard of the foglamps. You will be in for an eye opener.
 

Pentalab

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What do you consider "overheating"? When I first started tracking my base GT, I saw coolant temperatures around 230 degF and oil temperatures reaching almost 310 degF. At that point, the only changes I made from the OEM setup were brake pads, brake ducts, and NT-05 tires. If the Boss 302's run a lot hotter than that, I'm really surprised that Ford continued to release them after the first year without beefing up the cooling system. It's certainly possible that it was a gross oversight, but given the intended use for them, I have to be skeptical.

What kind of coolant/oil temperatures did you see before you changed the cooling system?

Something sure is amiss here. Terry is saying his stock GT had NO heating problems for the 1st 3 years. Yet you have the same base GT....and are seeing 230 F coolant temps..and 310 F oil temps ! So what gives ?

Both Kendal's megabuck oil-air cooler and the FRPP oil-air cooler are designed to be used in series with the ford .."oil cooler".. ( uses 200+ F coolant to.."cool" the 300F oil). It appears that Kendal's oil-air cooler can now only be used in conjunction with the ford 'oil cooler'..and not standalone. So it looks like the base GT owners are forced to buy the 'oil cooler' PLUS the FRPP /kendal oil-air cooler. Forget the ford oil-water cooler..and use a standalone air-oil cooler..with a T stat.

The FRPP oil-air cooler is expensive.....and does not have a T stat ! Kendal's has a T stat set for 180 F.

If you read the posts on mustang source.com..it appears that the ford 'oil cooler' initially results in the oil temps coming up really slow. Folks are saying it takes double the time to get the oil temps up to normal. I can see why. On start up, the eng coolant temps will be really low, like ambient..so cooling effectiveness of the oil-eng coolant cooler will be at max. Once the oil is up to temp, then the oil-eng coolant cooler is rendered ineffective. 200+F eng coolant (with perhaps a 50-50 water-glycol mix) won't be effective when trying to cool 300+ F oil.
 

Pentalab

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Even I know when to shut the F up, he has no clue. Maybe he didnt read Terrys post.

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Yeah I read it. Her claims no cooling issues for the 1st 3 years.....yet other's are seeing sky high water temps of 230 F and 310 oil temps.... and both are using the base GT. Something doesn't add up.

Terry wanted to enhance the aero on his front splitter..so reverse ducted the hood..and also blocked off the upper grille. Have you seen pix of his rvs ducted hood? It's a massive down slope...toward the front of the car. You can see the back side of the eng rad. It's located in a low pressure point.

My guess is the rvs ducted hood is acting like a venturi..sucking even more air out of the ducted rad compartment. With the upper grille blocked off, it will then suck even more air through the lower grille. With more air through the lower grille, the aero effect will be enhanced on the splitter...more downforce. So his blocked off upper grille works.... only when done in conjunction with a ducted rad..and a rvs ducted hood.. + splitter.

For folks with base GT's..and 230 F coolant temps and 310 F oil temps...I don't think this is your que to block off the upper grille just yet.
 

kcbrown

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Once the oil is up to temp, then the oil-eng coolant cooler is rendered ineffective. 200+F eng coolant (with perhaps a 50-50 water-glycol mix) won't be effective when trying to cool 300+ F oil.

Well, of course it will be effective, in that your oil temperatures will be lower with the cooler in place than without it. Cooling is a function of a temperature difference. And there is certainly a temperature difference here.

Remember, too, that the coolant temperature you're going by in the above is that of the coolant entering the radiator, but the oil cooler uses water exiting the radiator.

It looks to me like the oil cooler is more of an oil temperature stabilizer than anything else. Obviously it will keep the oil from coming up to temperature until the coolant temperature rises beyond a certain point.

However, if the surface area over which the oil and coolant are able to exchange heat is too limited, then the cooler will be limited in its ability to keep the oil temperature in check. And all of the heat exchange is happening within the relatively small area occupied by the sandwich plate. The real question, then, is whether or not that area really is sufficient as a heat transfer mechanism.


It therefore appears to me that the primary problem is the likely to be the heat dissipation capacity of the cooling system itself, with a possible secondary problem being that the heat exchange capacity of the oil/water interface is inadequate.

Put another way: if there is more than sufficient heat dissipation capacity in the radiator to keep the coolant temperatures down, then the oil temperatures should follow suit. If the problem is with the oil cooler, then coolant temperatures will remain low while the oil temperature goes out of bounds. If what you're seeing is the coolant temperatures going out of bounds, then the problem is not with the oil cooler!
 
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SoundGuyDave

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Terry wanted to enhance the aero on his front splitter..so reverse ducted the hood..and also blocked off the upper grille. Have you seen pix of his rvs ducted hood? It's a massive down slope...toward the front of the car. You can see the back side of the eng rad. It's located in a low pressure point.

My guess is the rvs ducted hood is acting like a venturi..sucking even more air out of the ducted rad compartment. With the upper grille blocked off, it will then suck even more air through the lower grille. With more air through the lower grille, the aero effect will be enhanced on the splitter...more downforce. So his blocked off upper grille works.... only when done in conjunction with a ducted rad..and a rvs ducted hood.. + splitter.

Admittedly, I am NOT an aeronautical engineer, but I don't think you gain downforce from a splitter by accelerating the airflow on the top surface... A splitter acts somewhat like the leading edge on a wing. On an aircraft, the longer path-length on the top (due to the curve) creates a low-pressure area relative to the higher-pressure shorter path underneath, and you wind up with lift. On a splitter, the air moving below the splitter is high-velocity, low pressure, and on top, where it runs into a whacking great air-dam (or radiator inlet, or...) you have low-velocity, high pressure air, and you generate downforce. With the way you're thinking about it, moving more air across the top of the splitter would only serve to reduce downforce. Period.

What Terry is doing with the ducted design isn't about creating additional downforce on the splitter blade itself, it's about reducing negative downforce from the un-vented underhood area. Think of all that air being jammed into both the upper and lower grille areas, rammed through the A/C condenser and radiator, and then going... where? On a stock setup, all that airflow is what makes the hood dance around at speed, and it's effectively acting like a parachute. This is creating negative downforce all by itself. Terry's ducting simply gives all that air a clean path to travel and reduces that parachute effect. Since the air isn't dead-end stagnating in the engine bay, he also doesn't need excess airflow across the radiator to keep things cool, and as a result was able to block off the upper grille, helping to minimize the "parachute effect" even further. If anything, in pure splitter force, the ducting probably pulled a little pressure off the blade. In terms of net downforce, though, the small loss at the blade is more than compensated for by the large negative-downforce reduction from the ducting.

You can get an analogous result by simply venting the hood, towards the front, and amplify that with a simple wicker-bill on the leading edge of the vent area. AND do it without a splitter. Only testing would determine whether there was sufficient airflow to keep the engine cool with a vented hood and a completely blocked upper grille, but it's certainly not out of the realm of possibility. Note, however, that this is definitely a "race car" mod that won't necessarily translate well to the street without all the ducting. At that point, you'd be relying on a fairly high-volume, high-pressure column of air entering the lower grille, which is something you're NOT going to get sitting on the tollway in rush-hour traffic on a 95*F summer day. Even boxing in the inlet to the radiator most likely wouldn't be sufficient there.

In short, though, I don't think the aero effects are working quite the way you think they are, and the blanking of the upper grille has little to do with the effects you're seeing.

For folks with base GT's..and 230 F coolant temps and 310 F oil temps...I don't think this is your que to block off the upper grille just yet.
That we can agree on.
 

SoundGuyDave

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The FRPP oil-air cooler is expensive.....and does not have a T stat ! Kendal's has a T stat set for 180 F.

Expensive? Not really. Price a good stacked-plate air/fluid heat exchanger, then add in the lines and fittings and you will rapidly approach the cost of the kit, and still have to engineer the routing and terminate the lines yourself.

If you read the posts on mustang source.com..it appears that the ford 'oil cooler' initially results in the oil temps coming up really slow. Folks are saying it takes double the time to get the oil temps up to normal. I can see why. On start up, the eng coolant temps will be really low, like ambient..so cooling effectiveness of the oil-eng coolant cooler will be at max. Once the oil is up to temp, then the oil-eng coolant cooler is rendered ineffective. 200+F eng coolant (with perhaps a 50-50 water-glycol mix) won't be effective when trying to cool 300+ F oil.
I think we can all agree that the factory "oil cooler" is a functional piece, but doesn't function the way that we want it to. Personally, the whole concept of using a 200*+ medium to cool engine oil in a high-performance application is all but insane. Whether you have a T-stat on it or not is immaterial other than with time taken to get up to temp. I would much rather have a 200* temp differential across the exchanger than an 80-90* differential. In particular since the cooling medium in question is also trying to keep the engine in one piece at the same time. On a street application, I would run a T-stat and a medium sized core, but on a race application, I would just blow it off and use a whacking great cooler core. It really doesn't take that long for the oil temps to come up to nominal, and in the meantime I'd prefer to remove the restriction and extra failure points inherent in a T-stat.
 

kcbrown

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Expensive? Not really. Price a good stacked-plate air/fluid heat exchanger, then add in the lines and fittings and you will rapidly approach the cost of the kit, and still have to engineer the routing and terminate the lines yourself.

I think we can all agree that the factory "oil cooler" is a functional piece, but doesn't function the way that we want it to. Personally, the whole concept of using a 200*+ medium to cool engine oil in a high-performance application is all but insane.

Actually, it's not, as long as the target temperature isn't too close to the operating temperature of the cooling fluid. And again, remember that the actual temperature of the cooling fluid (water) is that of the outlet side of the radiator, while the temperature you're going by here is the inlet side. In other words, you have to account for the drop in temperature of the cooling fluid prior to its use as a medium to cool the oil. 200F is likely to be on the high side for that.

The heat transfer coefficient of water is around two orders of magnitude greater than that of air. The ratio of the temperature differentials of the oil and water versus the oil and ambient air is about 2 or so (assume you're cooling oil at 300F. Water temp is at 200F on the outlet side of the radiator, while ambient air is at 100F). So all else being equal, the water-based cooler is about 50 (i.e., 100/2) times more efficient at cooling the oil.

To equal the water based cooler, the air-based cooler will have to have roughly 50 times the surface area of the water-based cooler. This is despite the fact that the water based cooler is, in the above ballpark example, using a cooling fluid that is 100 degrees hotter than the ambient air.


That's just a ballpark estimate, but you get the idea. The water based cooler is almost certainly more effective than you think. The main reason that adding an air-based oil cooler to the system results in better engine cooling is that it adds heat dissipation capacity to the overall system.

Again, only if the oil is exceeding temperature limits while the coolant temperature is staying in check is the oil cooler insufficient. Otherwise, physics alone says that the problem must be with the heat dissipation capacity of the cooling system itself, which means a larger radiator, better airflow, etc., are warranted. Adding an air-based oil cooler to the engine is one way of increasing that capacity.

Now, if adding capacity to the cooling system results in a much smaller drop in oil temperature than water temperature, then that would be an indication that the oil cooler is failing to transfer much additional heat away from the oil. In that event, it's likely that increasing the water flow through the oil cooler would remedy the situation, and it then becomes a question of how to go about doing that. If that proves impossible to do to a sufficient degree, then at that point there would be no choice but to add an air-based oil cooler to the system. Indeed, it's conceivable that the problem some are having with excessive oil temperatures is the result of insufficient water flow through the oil cooler, and I have to wonder if that is something that has been investigated by those who have experienced the problem.
 
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Whiskey11

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Actually, it's not, as long as the target temperature isn't too close to the operating temperature of the cooling fluid. And again, remember that the actual temperature of the cooling fluid (water) is that of the outlet side of the radiator, while the temperature you're going by here is the inlet side. In other words, you have to account for the drop in temperature of the cooling fluid prior to its use as a medium to cool the oil. 200F is likely to be on the high side for that.

The heat transfer coefficient of water is around two orders of magnitude greater than that of air. The ratio of the temperature differentials of the oil and water versus the oil and ambient air is about 2 or so (assume you're cooling oil at 300F. Water temp is at 200F on the outlet side of the radiator, while ambient air is at 100F). So all else being equal, the water-based cooler is about 50 (i.e., 100/2) times more efficient at cooling the oil.

To equal the water based cooler, the air-based cooler will have to have roughly 50 times the surface area of the water-based cooler. This is despite the fact that the water based cooler is, in the above ballpark example, using a cooling fluid that is 100 degrees hotter than the ambient air.


That's just a ballpark estimate, but you get the idea. The water based cooler is almost certainly more effective than you think. The main reason that adding an air-based oil cooler to the system results in better engine cooling is that it adds heat dissipation capacity to the overall system.

Again, only if the oil is exceeding temperature limits while the coolant temperature is staying in check is the oil cooler insufficient. Otherwise, physics alone says that the problem must be with the heat dissipation capacity of the cooling system itself, which means a larger radiator, better airflow, etc., are warranted. Adding an air-based oil cooler to the engine is one way of increasing that capacity.

Now, if adding capacity to the cooling system results in a much smaller drop in oil temperature than water temperature, then that would be an indication that the oil cooler is failing to transfer much additional heat away from the oil. In that event, it's likely that increasing the water flow through the oil cooler would remedy the situation, and it then becomes a question of how to go about doing that. If that proves impossible to do to a sufficient degree, then at that point there would be no choice but to add an air-based oil cooler to the system. Indeed, it's conceivable that the problem some are having with excessive oil temperatures is the result of insufficient water flow through the oil cooler, and I have to wonder if that is something that has been investigated by those who have experienced the problem.

If there is one thing that I have learned from water cooling PC's it's that the temperature delta between the hottest part of the loop and the coolest part is not as big as most people think. I would LOVE to see temperature probe data from the outlet of the engine's water jacket and after the radiator to see how much of a delta is there but I don't think it is as much as one would assume. In water cooling PC's that number is around 1-2ºC which isn't huge. We are talking about cooling CPU's that under load can reach temperatures in excess of 100ºC (max operating temperature for my 3770k is 105ºC and I've seen as high as 85ºC on my setup.

The biggest difference between a car and a computer water loop is the airflow. I can build up some pretty good pressure and air flow with my push/pull fan configuration but I doubt it comes close to the forces and flow the radiator on a car sees while the car is in motion. Hence why I would be interested to see what the temperature delta is between the hottest and coldest part of the loop.

As for the grill opening, well, a lot of that is done to reduce drag but I suspect opening the front grill more without venting the hood in some fashion more than stock will actually reduce radiator performance by allowing higher pressures in the engine bay because of the higher pooling of air that is in there that finds its way around the radiator. Even boxed in you will see a temporary increase in air flow through the radiator at lower speeds and then as you speed up the pressure differential between the front and rear of the radiator is going to be less than with the blocked off grill. The lower the pressure delta between the two, the less airflow there is through the radiator.
 

ddd4114

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If there is one thing that I have learned from water cooling PC's it's that the temperature delta between the hottest part of the loop and the coolest part is not as big as most people think. I would LOVE to see temperature probe data from the outlet of the engine's water jacket and after the radiator to see how much of a delta is there but I don't think it is as much as one would assume. In water cooling PC's that number is around 1-2ºC which isn't huge.
It depends on the system, the airflow, and the engine condition, but 10ºC is a pretty reasonable guess for a car on a track.
 

kcbrown

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If there is one thing that I have learned from water cooling PC's it's that the temperature delta between the hottest part of the loop and the coolest part is not as big as most people think. I would LOVE to see temperature probe data from the outlet of the engine's water jacket and after the radiator to see how much of a delta is there but I don't think it is as much as one would assume. In water cooling PC's that number is around 1-2ºC which isn't huge. We are talking about cooling CPU's that under load can reach temperatures in excess of 100ºC (max operating temperature for my 3770k is 105ºC and I've seen as high as 85ºC on my setup.

Data, such as this, suggests the delta to be somewhere between 30 and 60 degrees Fahrenheit for a typical automobile radiator.


As for the grill opening, well, a lot of that is done to reduce drag but I suspect opening the front grill more without venting the hood in some fashion more than stock will actually reduce radiator performance by allowing higher pressures in the engine bay because of the higher pooling of air that is in there that finds its way around the radiator. Even boxed in you will see a temporary increase in air flow through the radiator at lower speeds and then as you speed up the pressure differential between the front and rear of the radiator is going to be less than with the blocked off grill. The lower the pressure delta between the two, the less airflow there is through the radiator.
Yes, indeed. That's why you have to either add surface area (e.g., with a thicker radiator) or provide some way of evacuating the air behind the radiator more efficiently. A proper hood design will accomplish the latter. Adding an air-based oil cooler does the equivalent of the former, though it targets the oil directly, at the expense of raising the temperature of the air hitting the section of the radiator behind it.

It would be interesting to know how much of a difference the 2013 hood design makes compared with the 2012. Also, the GT500 hood has a cutout that looks like it should accomplish the same thing.
 

ddd4114

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Data, such as this, suggests the delta to be somewhere between 30 and 60 degrees Fahrenheit for a typical automobile radiator.
Maybe if the thermostat isn't fully open yet. If it is fully open (as it would be on a track), that temperature drop would be a lot less. I would think that 60 degF would seriously overcool the engine.
 

kcbrown

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Maybe if the thermostat isn't fully open yet. If it is fully open (as it would be on a track), that temperature drop would be a lot less. I would think that 60 degF would seriously overcool the engine.

That's possible. It would be very interesting to get real measurements of this under track conditions. I'm unable to find any data for those specific conditions.
 

SoundGuyDave

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While I cannot and will not argue the physics of liquid/liquid vs. liquid/air cooling, the test data you pointed out was obtained in a wind tunnel environment, using a Ford Grenada, 302 motor, A/C on, under 60MPH cruise condition. For our purposes, I would consider those testing conditions to be absolutely irrelevant. At Road America (four miles of fun, and a dozen corners), there is only ONE corner on the track where the apex speed is at or below 60mph. Additionally, WOT conditions under high load will generate quite a bit more thermal energy within the engine itself than you will see under 60mph cruise conditions.

Finally, I will absolutely accept your assertion that water is roughly 50 times more efficient than air as a cooling medium. That leads us to the design of the cooler itself.

Water/Oil cooler:

th

Stacked-plate Air/Oil cooler (picture may be tube and fin):

100062d1327427084t-frpp-boss-302-air-oil-cooler-now-available-frpp-cooler.jpg

For relative sizes, note the size of the oil filter adapter in each picture.

Three things to look at: First, surface area of the acutal heat exchanger... With the water/oil design, the exchanger is either located in the oil filter adapter block, in which case it's tiny, or it's located in the lower hose, where it may be larger, but then provides additional flow restriction. I submit that either way, the air/oil cooler has more than the aforementioned 50 times the surface area. Second, all the thermal energy removed from the oil has to go somewhere; it doesn't just disappear. With either design, it impacts the engine cooling, but they differ in exactly how that happens. With the water/oil cooler, the thermal energy is dumped directly into the coolant, after the radiator, as it leads into the block. This will tax the engine cooling system, and will push it closer to it's overall thermal capacity. With the air/oil cooler, assuming that it is mounted in the airflow in front of the radiator, it will result in a somewhat localized increase in radiator inlet air temperature directly behind the cooler. While this will reduce the efficiency of the radiator itself, I seriously doubt that it will have anywhere near the impact of the water/oil exchanger on net thermal capacity. If, OTOH, you were to set up a dedicated air path for the cooler, it would have NO direct effect on the engine cooling whatsoever. Third, you'd be hard pressed to find many examples of purpose-built racers using water/oil cooling for any fluids that involve the engine cooling system. The Factory Five GTM is an excellent example of this. This is a rear-engine car, with a front-mounted boxed/ducted radiator, and has external coolers for both engine oil as well as transaxle. Both of those coolers are mounted in the rear, exhausting into the diffuser. The FR500C has transmission and differential coolers mounted under the body in the area formerly occupied by the stock fuel tank. There's a Porsche 911 RSR in my area that has a stacked-plate oil cooler mounted in front of one of the wheelwells, and I believe that to be a factory piece. Nascar COT have coolers for just about everything, including dedicated valvetrain coolers(!), and those are either tucked into the inlet air boxing for the radiator or act as passive radiators without engineered airflow. The COT is an interesting piece. The radiator itself DOES include a water/oil heat exchanger, but done just a little bit differently than the Boss302 piece:

th


In this case, there is a 10-plate exchanger mounted within the top half of a double-pass radiator, which allows the radiator itself to shed the acquired BTUs prior to returning the coolant to the engine itself. The radiator is also bloody HUGE compared to street car applications, and has engineered in the extra thermal capacity missing from an add-on system like the Boss302 piece.
 

kcbrown

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While I cannot and will not argue the physics of liquid/liquid vs. liquid/air cooling, the test data you pointed out was obtained in a wind tunnel environment, using a Ford Grenada, 302 motor, A/C on, under 60MPH cruise condition. For our purposes, I would consider those testing conditions to be absolutely irrelevant.

Well, maybe. It would be interesting to get some data showing the actual temperatures involved here. That would make it much easier to know what's going on here.


At Road America (four miles of fun, and a dozen corners), there is only ONE corner on the track where the apex speed is at or below 60mph. Additionally, WOT conditions under high load will generate quite a bit more thermal energy within the engine itself than you will see under 60mph cruise conditions.
But remember that the faster you're going, the greater the airflow through the radiator and, thus, the greater the amount of heat transferred by it. It appears that the heat transfer rate is approximately linearly proportional to the airflow velocity, but there are massive caveats associated with that. Working out heat transfer turns out to be massively complicated.


Finally, I will absolutely accept your assertion that water is roughly 50 times more efficient than air as a cooling medium.
Well, actually, about 100 times. The factor of 50 comes from accounting for the ratio of temperature differences between the two scenarios. But whether it's 50 or 100, the point there is only that the water based cooler is, from a theoretical standpoint (and, it seems, from experience as well), more effective than one might otherwise think. Basically, there are some here who believe it to be detrimental, and that is a claim I'm deeply skeptical of, just based on the physics.


That leads us to the design of the cooler itself.
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Yep, I completely agree, it's almost certain the air-based oil cooler has sufficiently greater area that it helps. My argument is not that the air-based cooler is insufficient, nor that the water-based cooler is sufficient of itself, only that the physics of the situation is such that I see no reason to believe that adding an air-based cooler to the situation will achieve substantially better results than would adding radiator capacity, possibly combined with (somehow) increasing the coolant flow through the water-based cooler.

This is where experimentation rules the day, particularly experimentation that changes only one variable at a time. Putting temperature probes at various locations in the system is going to be a necessity for determining what's really going on. You'll want probes at the inlet side of the radiator, the outlet side of the radiator, at the oil cooler (for measuring the oil temperature there), and possibly other locations as well. You'd also want air temperature and velocity probes behind the radiator. Then you start changing things, one item at a time: hood design, grill opening characteristics, radiator size. The data gathered by all the probes should give you an idea of what those changes are actually doing.


In any case, what is completely unclear to me at the moment is whether, under overheating conditions, the coolant temperature is remaining in check. My impression, because the car is going into limp mode, is that it is not, and that suggests that additional heat transfer capacity at the radiator is in order. If merely cooling the oil directly were sufficient without any other changes, then why would Cooltech's research indicate that the optimum solution involves keeping the water-based cooler in place?


There is one thing about the water-based cooler's design that surprises me: I would have expected the outlet side of its water flow to go to the inlet side of the radiator. But instead, it goes back into the inlet side of the engine. I have to wonder if the effectiveness would be improved by making that one change.
 

Sky Render

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Pentalab, the more of your posts I read, the more I become convinced you have no bloody clue how physics, suspension design, thermodynamics, or just about anything actually works. What makes things even worse is that you seem to think you are correct even when other people clearly point out you are not.

Ask yourself: what is more likely? That you are indeed the smartest person on this forum and that everyone else doesn't know what they are talking about, or that maybe--just maybe--you have more to learn than you think you do.
 

Pentalab

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Pentalab, the more of your posts I read, the more I become convinced you have no bloody clue how physics, suspension design, thermodynamics, or just about anything actually works. What makes things even worse is that you seem to think you are correct even when other people clearly point out you are not.

Ask yourself: what is more likely? That you are indeed the smartest person on this forum and that everyone else doesn't know what they are talking about, or that maybe--just maybe--you have more to learn than you think you do.

Nasa has a sign up that sez.... "one test is worth a 1000 opinions". None of this cooling discussion is rocket science. If you are generating XXX btu's.... you require a cooling scheme that will dump XXX btu's.... and perhaps a bit more. It's a case of thermal management. You want to end up with a cooling system, such that cylinder head temps are kept in check, and don't exceed XXX deg F. To pull that off, you require a water pump/ eng rad setup, with enough airflow through the rad. IF you can keep the eng coolant temps in check, your oil temps will drop off too.... but in some cases, not enough. A HE, using water ( NOT hot eng coolant) to extract the heat of the hot oil..then the heated water fed to a 2nd HE..( with air through the 2nd HE) would work. IE: a closed loop setup, with 2 x HE's, one pump. A simpler approach would be a bar + plate type oil cooler..with of course air through the cooler...+ a T stat.

"For reference, we had NO oil cooler NOR an aftermarket radiator in our Mustang GT for the first 3 years of track use. With 430+ whp and ambient temps often above 100°F - and usually 2 people double-driving this car at each event - for 30+ events per year, we had NO oil OR coolant overheating problems, while setting track records. No problemo. We use 15W50 Mobil1 oil and change it religiously. That was the extent of the changes to the cooling or oiling for the first 3 years. "

"The factory coolant/oil "cooler" is NOT a very good design that, we feel strongly, SHOULD BE REMOVED. It IS an oil HEATER. The GTs don't have this design and they DON'T overheat on track.

"But we HAVE REMOVED these silly trans scoops on some of our customers' Boss302s and SOME overheating complaints HAVE BEEN REDUCED. We've also replaced the Boss302 coolant-based oil cooler with the GT radiator hoses added an external fluid-to-air oil cooler with very positive results. We done both to a customer's heavily tracked boss302, which we also added external gauges to, and oil temps dropped markedly".

" See, the "scoop" is trying to divert under car air flow up towards to the Getrag MT-82 TRAIN WRECK wreck of a transmission (that can and does overheat badly - we turned 3rd gear blue before it FAILED)."

"When we wanted to MAKE A MORE FUNCTIONAL front splitter, we completely blocked off the upper grill (oh n0es!!11!!one!!) and all of the incoming airflow for the radiator now comes from just the lower opening, sealed to the a/c condenser (gasp!) and radiator.

"What do you consider "overheating"? When I first started tracking my BASE GT, I saw coolant temperatures around 230 degF and oil temperatures reaching almost 310 degF. If the Boss 302's run a lot hotter than that, I'm really surprised that Ford continued to release them after the first year without beefing up the cooling system. It's certainly possible that it was a gross oversight, but given the intended use for them, I have to be skeptical. "


"As the front of the car slows down the air without a diffuser, this is the ideal place for an inlet. A splitter is commonly used here, serving to increase the amount of downforce at the front of the car. The airstream is brought to stagnation above the splitter by an air dam, causing an area of high pressure. Below the splitter, the air is redirected away from the stagnation zone and is accelerated, causing the pressure to drop. This, combined with the high pressure over the splitter, creates downforce. The larger the area of the splitter, the more downforce is generated.

Ok, so we have low pressure below the splitter...and high pressure above the splitter. To get the splitter to work, the air above the splitter needs to be stagnated..hence the air dam. IF the upper grille is blocked off..AND hood vents are used.... the air is gonna scream through the lower grille. If the lower grille is located above the air dam, this higher velocity airflow through the lower grille may or may not affect splitter performance. It would depend if a dam was used, how big, and how high above any dam the lower grille is located.

It appears the MT-82 "train wreck" tranny still requires some cooling...like a real one this time....small rad. If base GT's have 230 F water temps and 310 F oil temps, the base GT has insufficient cooling. For you folks with sky high water + oil temps...did any of you measure the cylinder head temps ???

As for the discussion on water vs air cooling... in large metal tubes, used for broadcast use, air cooling will remove 50 watts per square cm. Vapor phase cooling will remove 135 watts per sq cm. Water will remove 1000 watts per sq cm. 1 watt = 3.41 btu's per hr. Of course you have to factor in the temp of the cooling water..+ air temps, etc. I design cooling systems for the above, so have some experience with it.... but its a different application from a mustang.

We used vapor phase cooling on one of the diesel standby generator's at work. The theory is when you turn 100 deg C water into 100deg C steam, you release a tremendous amount of energy. The steam is condensed back to water..and cooled just below 100 deg C. Turning 100 deg C water to 100 deg C steam is 20 x more eff vs raising 99 deg C water to 100 deg C water.

Some of the diesel standby generators I looked after were V16's..with pistons the size of paint cans. Eng rads were the size of a garage door, and a 98,000 cfm fan used to pull air past the rad. Turbo HE cooling was done via an air to air HE....stacked on top of the main eng rad. Any errors in these cooling systems can be very costly.

In my particular case, I have 6 x rads to cool via air through both the upper and lower grille. If an oil cooler is used, then it's up to 7. I require all the air I can get... hence the 7 bar upper grille....and lower chin spoiler. I'm currently looking at vented hoods.... to relieve pressure. I don't want water getting through them though. I designed a scheme where the louvers would only begin to open at 30 mph..and open more with increased speeds..( higher underhood pressures). HVAC systems use something similar to relieve pressure in commercial buildings. Some positive pressure is retained....to keep dust out.

At our local sc track, they will only allow 100% distilled water (+ water wetter) to be used in eng rads.....no glycol. Some of the cars will use a higher pressure in the coolant loop. The boiling point will be raised considerably (think pressure cooker theory). You can extract more heat with 100% distilled water vs a 50-50 water glycol mix..esp if water wetter is used.

Impact pressure from wind goes up to the square of the wind velocity. 70 mph is double the pressure of 50 mph. 70 mph is triple. 100 mph is quadruple. 111.8 mph is 5 x the pressure. These cars are as streamlined as a brick. The cd is nothing to write home about.

As a rough rule of thumb, to stuff double the air through a small orfice, you require 4 x the pressure.

For folks at higher elevations it all gets worse. The air density is thinner of course. The weight of the air is way less. ( mass airflow rate factors in the weight of the air). At 5000', you require 20% more cfm to get the same mass airflow. You also require 20% more pressure as well. The problem is at 100 mph, your cfm through your rads stays the same, but the weight of the air is less. You lose it right there. Your eng fan (or say HE fan if a blower is used) needs another 20% cfm. It also requires another 20% more pressure. Wait, it gets worse. Fans are rated for sea level..not elevation. A series of calculations is then done to determine what sea level rated fan can be used to work at 5000'. The results will make you gag. Works out to aprx another 57% cfm required..and a helluva lot more pressure. Worse case is higher ambient temps + higher elevations.

I'm no suspension expert....suffice to say the PHB setup is extremely limited. If you saw the go pro video's of the rear tires going from being tucked into the wheel wells to extending way out past the wheel well, during auto cross, you would need little convincing that a watts link is the real answer. I'm not impressed with the oem traction lock lsd either....I replaced it with a tru-trac. The oem GT suspension on my 2010 leaves a lot to be desired. (nose dive under braking, back ends lifts. Front end rises, back end squats with acceleration. Flops about during cornering.) I replaced all of it.

Back to cooling. What thresholds are you folks using for the high and low speed eng fan ?? oem is 204F coolant temps for the low speed fan...and 209F coolant temps for the high speed fan. Low speed fan is adjustable from 170-230 F. High speed is adjustable from 180-240 F.

If you drop them down a bit... you won't have to play.... "catchup".
 

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