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Trying to finalize my cooling setup and am wondering if anyone has any experience with this company? DeltaPAG. I cannot seem to locate the SPAL 14" brushless fan and found these guys while searching.

Also wondering if there is a link to some sort of formula for calculating core size? Maybe it was manufacturer specific but early in the thread Hydrodynamic posted what looked like radiator size to HP efficiency.. Seems like it would be a useful exercise to ballpark.
 
HYDRODYNAMIC said:
The stock 6.0 water pump should flow 20GPM at 2000RPM and 66GPM at 6000RPM
The radiator should remove 196,000BTU/Hr. at 140ETD at 20GPM and 245,000 BTU/Hr. at 140ETD at 66GPM which is equivalent to 77-96HP. 140ETD means 220 degree fluid entering with 80 degree ambient air cooling the radiator.
Rule of thumb: About one third of the heat generated by the engine goes into the coolant/water mixture and must be dissipated by the radiator. That would mean the 96HP x 3 = 288HP, but radiators of this size are commonly rated at 600HP. So I am at a loss of the industrial ratings vs what is working. Still digging
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I believe this is all based off of the amount of horse power that the engine is continuously using, which is why 288HP of cooling is sufficient for a 600hp engine. Which is why the cooling system for a 600hp desert or short coarse truck would need to be larger than a 600hp crawler.
 
93blackxj said:
I believe this is all based off of the amount of horse power that the engine is continuously using, which is why 288HP of cooling is sufficient for a 600hp engine. Which is why the cooling system for a 600hp desert or short coarse truck would need to be larger than a 600hp crawler.
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Exactly.
Some 1200hp pulling tractors done even have radiators, just a tank to keep water in the block. They don’t run long enough to get hot.
Block size and design and materials will determine how much heat it can hold or accumulate before the cooling system must remove heat.
 
I guess I will give an update on this subject. I bought a brushless Spal 10" fan for nearly $500. I tested it against and 40 year old 10" brushed fan and a modern Spal 10" brushed fan. All these fans were to fit in my Delorean. I really expected vast improvements in efficiency. In 40 years. Not only was the old fan heavy, but the old fan blades looked like a kid made them compared to the modern blade designs.

The tests included amp draw and CFM of air moved.

You may not believe this, but there was no clear winner. The modern brushed fan drew less power than the old fan, but moved a comparable less air. The brushless fan could move a lot more air than the other two, but it drew a lot more amps also. The brushless fan has the ability to run at differnt speeds. If you dial it down to move the same air as the 40 year old fan, it uses about the same amps.

If you need the controllability of the brushless, it's a great way to go, but if your thinking of lots less power, it's just not so.

I ended up installing the modern brushed Spal fans in my car because one of the two old fans burned up. The Delorean is know to be over cooled and under sized on wiring. So I don't mind a little less CFM and less amp draw.

PS, anybody want to buy a slightly used brushless fan?
 
On thinking about my last post, I feel I didn't give a very accurate update. The guy I had do my testing was an electronics engineer and he did a great job. (For nothing I might add) He just likes to test stuff. He made a very elaborate test rig. He wrote a report on each fan/motor in multiple emails. I think I did him a disservice when I use the word "about".

So here are some numbers that you can compare.

The 40 year old OEM fan moved 1670 CFM at 12.5 amps. Or 133 CFM per amp.

The modern, brushed, Spal fan moved 1612 CFM at 8.7 amps. Or 185 CFM per amp.

The Spal brushless fan moved 1935 CFM at 13.2 amps. Or 146 CFM per amp.

I do have to point out that the brushless fan is dialed down (via a controller) to draw approximately the same amperage as the others. If you let lt go to max draw, the numbers get worse. (The CFM goes up, but the amps go up quicker)


Looking at this, I would say the modern brushed fan is the clear winner in CFM/amp and I'm glad that's what I have on the car now.

The one other thing I might mention is when you go to the Spal site and look at the differnt brushless fans, the motors all look the same. They have multiple fan diameters, but the motor looks identical. So it maybe that the motor is not sized correctly for a 10" fan. Maybe the efficiency goes way up with a 16" fan because that's what they probably designed around.
 
I think there is a critical element that gets left out in those numbers, vacuum pulled. The pressure delta across the fan blade makes a huge difference. My experience with pump curves says working pressure at volume moved is how you get to wattage drawn (and motor size as a result) and those are not linearly connected in a centrifugal though out a speed range . Run a pump at full speed outside of its pressure curve and all you get is inefficiency.

The fan blade geometry as well as the motor attached create a symbiosis that need to then be paired with a working environment they were designed for. The brushless fan you tested may need to pull through a radiator core and pull some real load to show it's true efficiency colors. It also may not, but I think the numbers are short of the full picture without a few more data points of a variable that makes a large difference.
 
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WaterH said:
The 40 year old OEM fan moved 1670 CFM at 12.5 amps. Or 133 CFM per amp.

The modern, brushed, Spal fan moved 1612 CFM at 8.7 amps. Or 185 CFM per amp.

The Spal brushless fan moved 1935 CFM at 13.2 amps. Or 146 CFM per amp.
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10" brushless fan is 1331 cfm @ free air conditions (4,000 RPM) So not sure how that was measured, but I would consider this data comparative at best.

The 10" brushless fan peak total efficiency is ~41%. Used on a thin low restriction core it would likely be in the 25% range. This fan will draw in excess of 30 amps depending on the working point.

A 10" SPAL paddle blade brushed fan 1103 cfm, has ~27% peak efficiency, and is in the same 25% range at similar working pressure.


SPAL Brushless fans will have fixed RPM within some limits where as the brushed performance will change with voltage, so you want to account for the voltage at the fan also. Fan power is cubic with rpm, so the last rpm increase you use is much more expensive power wise than the previous.
 
Satan's_Minion said:
10" brushless fan is 1331 cfm @ free air conditions (4,000 RPM) So not sure how that was measured, but I would consider this data comparative at best.

The 10" brushless fan peak total efficiency is ~41%. Used on a thin low restriction core it would likely be in the 25% range. This fan will draw in excess of 30 amps depending on the working point.

A 10" SPAL paddle blade brushed fan 1103 cfm, has ~27% peak efficiency, and is in the same 25% range at similar working pressure.


SPAL Brushless fans will have fixed RPM within some limits where as the brushed performance will change with voltage, so you want to account for the voltage at the fan also. Fan power is cubic with rpm, so the last rpm increase you use is much more expensive power wise than the previous.
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Yes, the numbers were comparative. All were at 13 volts with no restrictions. Yes the brushed fans would go up and down with voltage. The brushless fan was tested at 15 volts and didn't change. If you put a radiator core in front the amp draw goes up. On the brushless for example, it went to 27 amps.

Where did you get those numbers? He tested the brushless at 4000 rpm and got over 2000 CFM.

In any case, it sounds like you know more about it than me, but these tests were comparable.
 
WaterH said:
Where did you get those numbers? He tested the brushless at 4000 rpm and got over 2000 CFM.
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SPAL Test data. That's why I was asking HOW he measured it.

I would expect the best inexpensive test you could do would build a small plenum out of carboard and grid it off with wire into sections. These should be similar dimensions to the business end of your anemometer. Then apply the velocity measured in each grid to the corresponding area, make sure to consider airflow direction (+/-), and sum all of these airflows.

Best would be to do that with it mounted to the heat exchanger stack because who cares what the fans do at free air...
 
Even though the brushless fan motors may look similar. I believe they are programmed for different speeds and loads based on the blade design.
Example the 17” vs the 14”. Free air the 17” is more efficient. Add a restriction and it falls on it’s face compared to the 14” which will pull more amps and keep the air moving.
Point is the fan motor and blade needs to match the core/restrictions for total cooling efficiency.
 
My engineer thought that CFM might not be a fair comparison, so he also tested thrust. He mounted the fans on a frictionless system and measured how much they could pull in grams. The numbers were somewhat similar to the CFM numbers. Not sure if that adds anything to the discussion.
 
It always helps to measure what you want rather than a proxy for what you want.


If you really care that much you should probably just fill up a radiator with hot water from your tap and measure how long it takes for each fan to drop the temp from X to Y.
 
WaterH said:
Looking at this, I would say the modern brushed fan is the clear winner in CFM/amp and I'm glad that's what I have on the car now.
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I don't understand why that's remotely relevant. You want the fan that pulls the most air given the restrictions in the vehicle (air access, core thickness etc) whatever the amps may be.
Just size your circuit for the amps pulled.

If a brushless fan pulls 30 amps but moves twice the amount of air than the brushed one at 8 amps, who gives a shit that the brushless fan uses more amps? Just size your circuit for 30 amps and enjoy the extra cooling power.
 
Bebop said:
I don't understand why that's remotely relevant. You want the fan that pulls the most air given the restrictions in the vehicle (air access, core thickness etc) whatever the amps may be.
Just size your circuit for the amps pulled.

If a brushless fan pulls 30 amps but moves twice the amount of air than the brushed one at 8 amps, who gives a shit that the brushless fan uses more amps? Just size your circuit for 30 amps and enjoy the extra cooling power.
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I mentioned before. (Maybe you missed it.) The Delorean is known for having an over powered cooling system and undersizing the wiring. (On everything) So most Delorean owners are changing out all their lights for LEDs because the stock incandescent lights make the wire bundles hot. The stock wiring would melt if you ran 30 amps to the fans. (It actually would be closer to 60 on two fans) Could I upgrade the wiring, sure, but it's not my thing. A lot easier to just change to a fan setup that pulls less amps. I would prefer that it pulls the same or more air, but like Mick said "you can't always get what you want."
 
Oh.

Sounds like a poor excuse to not do the right thing, but yeah, I missed that part, you're correct.
 
Bebop said:
Oh.

Sounds like a poor excuse to not do the right thing, but yeah, I missed that part, you're correct.
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If I need it, I will do it. But I had one of the stock fans quit and I drove a 120 mile trip in 90+ temps. The one fan did fine. That was with the 40 year old tech. I think the new ones should be fine.
 
WaterH said:
I mentioned before. (Maybe you missed it.) The Delorean is known for having an over powered cooling system and undersizing the wiring. (On everything) So most Delorean owners are changing out all their lights for LEDs because the stock incandescent lights make the wire bundles hot. The stock wiring would melt if you ran 30 amps to the fans. (It actually would be closer to 60 on two fans) Could I upgrade the wiring, sure, but it's not my thing. A lot easier to just change to a fan setup that pulls less amps. I would prefer that it pulls the same or more air, but like Mick said "you can't always get what you want."
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You know that if you go brushless with a smart temp switch the fan will only pulls what it needs and if the cooling system is oversized then that means the fan will run at a minimum and be more efficient than a fixed output fan that is wasting power moving air that doesn’t need to be moved.
 
HYDRODYNAMIC said:
You know that if you go brushless with a smart temp switch the fan will only pulls what it needs and if the cooling system is oversized then that means the fan will run at a minimum and be more efficient than a fixed output fan that is wasting power moving air that doesn’t need to be moved.
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I did buy a temp switch with it for testing. But in his testing when he dialed the fan down to the same amps, it pulled less air. So assuming the smart temp sender did the same, it would not be less amps. The other issue would be if it got hot for some reason and I had two fans draw 60 amps, I would probably have a fire. Fire is the number one destroyer of Deloreans. (Usually it's the junk fuel lines)

Also, I paid almost $500 for this one fan. (And sensor) I was able to buy the duel Spal fan and shroud for less than $300. I wouldn't have to send another $500 because the sensor can run two fans, but still to set this up would have been another $300 and I would have to make the shroud. Sense I wouldn't be comfortable with the possibility of melting wires, I would have to rewire it. I really wanted it, but it just became too much. Believe me when I say, it sucks I spent $500 for a fan and sensor to sit on my shelf. Maybe I'll find a use for it on another project.
 
HYDRODYNAMIC said:
The GEN 2 motors which are the current ones can run analog, PWM, and to ground to turn on. The GEN 1 had to have a signal and is inverse of the GEN2. I believe the same goes for GM motors being controlled similar to GEN1 motors.
I believe the 10” brushless is a newer release and should only be GEN2.
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Are you saying that in the SPAL SBL-YAX PT or PT10 wiring diagrams if you want to run full speed switched 12V you would need to run the white sensor wire to 12V switch and the yellow wire to ground?
 

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D.T.Starr said:
Are you saying that in the SPAL SBL-YAX PT or PT10 wiring diagrams if you want to run full speed switched 12V you would need to run the white sensor wire to 12V switch and the yellow wire to ground?
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Yellow is not connected in that case.
 
Even if the temp sensor is not being used? Where would the signal circuit get to ground?
 
I read hydrodynamic post to mean that one could run the brushless fans without the PWN, so I did a little test. I can confirm that without the temperature sensor wired in, connecting the white wire to 12V with yellow disconnected does NOT actuate the SPAL brushless fan in a SBL-YAX-PT10 harness. Nothing happens.
I did not try white to 12V and Yellow to ground.
 
D.T.Starr said:
I read hydrodynamic post to mean that one could run the brushless fans without the PWN, so I did a little test. I can confirm that without the temperature sensor wired in, connecting the white wire to 12V with yellow disconnected does NOT actuate the SPAL brushless fan in a SBL-YAX-PT10 harness. Nothing happens.
I did not try white to 12V and Yellow to ground.
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The sensor white goes to ground.
The yellow switched goes to power.
You need both connected to run the brushless direct.
The reasoning is that you would run the white wire on a old style temp switch that contacts to ground. The yellow is switched on and off. Otherwise the fan would run when the power is turned off or there would be no temp switch to turn it off or on.
 
Hello, I see alot of discussion on brushless cooling, so I thought I would chime in. I work for Delta PAG and they make some amazing brushless cooling systems, fans,
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waterpumps & digital controls. You should check them out deltapag.com

Also, thought it's important to point out that efficiency (CFM/amp) is very important as you would always want to minimize power consumption for every unit of work. Delta PAG's fans are very unique and are 25% more efficient than its closest competitor
 
DeltaPAGJohn - can you give some background on PAG? As a company do you develop and build the fans and controllers? Are these sold to vehicle OEMs?
 
None of it look waterproof / rugged to me.
 
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