More and larger cooling fans

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I have a hayden 3710 16" fan i want to use to improve my cooling system.

I was thinking i would trim the stock fan shroud and replace the stock 12" fan and then boom: airflow is improved by 4 inches. What worries me is the specs of the 3710 say 1500cfm. A guide i found said a v6 needs 2000cfm. Has anyone had any luck switching to larger fans like this?

So maybe i will strap the 3710 on the front of the radiator as a push. But now i am worried it may pull too much amps and blow my fan system. I can buy or wire a relay harness but is it really necessary? The 3710 is rated 20.40amps, but i do not know how to trace back the fan system for capacity or the existing fan specs.

I live in a tropical climate and need real ultimate cooling.
 
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I wouldn't screw with the cooling system if it isn't broken, I'm not sure that a larger fan is necessarily better, given that pressure isn't exactly an axial fan's strong suit, a smaller fan that spins faster and/or has a better blade design may net a higher airflow across the radiator than a bigger fan with a less optimal blade design that spins at a lower speed.
 
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I live in a tropical climate and need real ultimate cooling.

Did you consider to alter your coolant/water ratio? Going from 50:50 to 30:70
coolant/water will help with heat transfer. That's what racing teams use to do.
We've discussed this question in the past. Water has a superior heat capacity
compared to glycol. However I agree with others here: Why? What's the issue?
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Infomercial

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Yes I always do one gallon of coolant concentrate in my 3 gallon system and 2 bottles of additive containing anti corrosion and surface tension reducer. The rest is purified water.

I have also considered getting a performance radiator and lower temp thermostat.

The big problem is heat transfer is not 100%, more air would get me closer. The fan spinning less time would improve its reliability, while holding temp more precisely would improve the entire system.

Speaking of fan reliability, I am leaning toward a push/pull setup to allow safe operation after the failure of one fan.

Theres a whole lot of win in making the systems of your vehicle more efficient and reliable.
 

Infomercial

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It's a 2007 v6 mustang with 230,000 miles. Last time I checked the temp via obd2 is when I bought it, so I'll do it again before this cooling overhaul. It was 212 or 219f, whatever it's supposed to be.

I've had 2 different gauge clusters in this car. They each had different positions on the temp gauge when at temp. This one is slightly below half, which is pretty good I'd say!

My car is running and performing great. I thank everyone for the concern.


I have ordered a direct replacement shroud and fan, while not oem brand it may be more reliable than the original.
 
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Make sure that the radiator isn't plugged. I've seen where the bottom 1/3 of a radiator is plugged with mineral deposits. And that lead to several fan clutch replacements until someone noticed that the bottom of the radiator remained cool.

Not sure how that happens unless it has a leak and someone is continually topping it off with very hard well water.
 
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So it sounds like you're trying to build in more cooling capacity, not trying to solve a current cooling problem, right?

I don't know Mustangs--maybe somebody who does will find this thread--but I just looked at fans and radiators on Rockauto.

The same fan part numbers are specified for all three engine options: 4.0 V6, 4.6 V8 and 5.4 supercharged V8. That suggests to me that the stock fan probably flows plenty for the V6. It you want to make an upgrade, maybe a bigger radiator will give the increased capacity you're looking for.

According to Rockauto, the V6 and 4.6 both take the same radiator, with a 1-inch core and 1.5 inch inlet/outlets. The 5.4 radiator has a 1.5-inch core and bigger inlet/outlet sizes. It also looks like it might mount a little differently, but I'm not sure about that.

If this were my project, I would look for a performance radiator that fits the 4.0/4.6 application. Also make sure the A/C condenser and current radiator fins are clean and clear of debris.
 
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I've done a bunch of experimenting with powerful computer fans when there is a restriction like a radiator either in front of or behind the fan blades, moving the fan orientation when at speed to push against or pull from a restriction, like a radiator, or Ac condenser.

Almost every fan is not only quieter, but moves more air, when it is a pusher fan.
in the case of pushing or pulling, either works better the farther from the blades the impeller is, but a puller fan placed too close to the radiator just seems to stall the blades, the fan speeds up, makes lots more noise and moves a fraction of the air, compared to it it were just a little bit further away from the restriction.

A bigger fan is not necessarily more effective.

More rpm usually is more effective as long as the airfoil blades are not stalled from too much resistance.

CFM ratings are very misleading. They are taken my measuring velocity of air moved, when there is NO restriction to flow, then doing some math with fan diameter and coming up with some magic number designed to impress. The first problem with this is the velocity measured, it likely just to one side of one of the hub supports, where the air is accelerated around the obstacle.
Obviously a fan in front of or behind a radiator is restricted, so a fan designed for super high CFM, could perform much worse than one with a higher static pressure rating in such an application, and one with a huge static pressure rating in free air will seem to be underperforming, in comparison to teh high CFM fan, when there is no restriction to flow.

A high static pressure fan impeller usually has forward jutting, scythe like wider blades with a lesser angle of attack. High CFM blades are usually straighter, more numerous and angled steeper. Most fans are somewhere inbetween, but high pressure and high CFM can be a sweet spot of RPM and blade design with the amount of resistance and the distance from teh resistance all being huge factors in the overall efficacy. The CFM ratings should be viewed suspiciously, as should the amp ratings

The amp rating of a fan might be what the fan uses at 12vdc, it might also just be the start up surge. I've seen both, and do not trust any published rating until I confirm it, not only at 12v, but at 14.8v too as I tend to overwire for minimal voltage drop. I see far more fan's ratings correspond to their start up surge, rather then their draw at a steady 12v once already spinning but have not tested many radiator brushed motor fans. So I could easily be wrong.

You seem to be looking for an excuse to use the fan you already have, hoping it does something, but not really sure if it is needed or would do anything but make the alternator work harder and make more noise in the process. Each 25 amps the alternator has to produce eats up about 1HP, as alternators are only about 55% efficient and there are pulley and belt and Diode losses as well.
1HP=745.7 watts. 25 amps at 14 volts is 350 watts. Adding an actual 20 amp fan can simply add to the heat load for the radiator to remove. If the fan blades are stalled from too close a location to the restriction, then one cannot expect more cooling. So just slapping a fan on is no guarantee of anything other than time consumed.

if the cooling is questionable and it is confirmed to be running too hot, I like the radiator for the V8 idea the best.

Also, If the engine has a computer, it is expecting its thermostat to be OEM temp. A cooler T stat will likely just kill MPG and could be a short lived solution to running too hot. If the radiator or the fans on it are not performing as they should, a cooler t stat would just take slightly longer for it to run too hot, as the if overheating both a 165 or 1 195 t stat would be fully open, the 165 would just begin opening sooner.

Be very careful when powering unmounted fans, but in some applications, it is the best way to find out the ideal location/orientation in which to mount them, or decide against doing so all together.
 
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I've done a bunch of experimenting with powerful computer fans

Using the words 'powerful' and 'computer fans' in one single sentence is irritating me to say the least.


It's a 2007 v6 mustang with 230,000 miles. Last time I checked the temp via obd2 is when I bought it, so I'll do it again before this cooling overhaul. It was 212 or 219f, whatever it's supposed to be.

All my cars do run hotter.
.
 

Astro14

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On a 230,000 mile car, I would replace the radiator and the water pump and flush the block before addressing air flow.

Coolant circulation rate, internal corrosion, and blockages are likely causes of reduced performance at that mileage and won’t be helped by increased airflow.
 
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Does it overheat as is? Use an OBD scanner to get the real temperature - the only accurate gauge in any Ford cluster is the speedometer. Gas, oil pressure, coolant temp are all varying degrees of fake.

But unless it's overheating, why mess with it? One of the reasons modern engine las so long is how well they regulate temperature. 200-220F is pretty much ideal for a modern gas engine.

If you want the ultimate cooling for beating on it, go with a mechanical fan. You'll never move as much air as a mechanical fan infront of an engine that's screaming. If it's the 3.8, maybe swap in the water pump , fan and clutch from a 4.2L f150? I'm joking there ... kinda ... But a common upgrade in the early days of the JK Wrangler was the mexican market clutch fan.
 

Infomercial

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It does not overheat. The new fan and shroud i ordered arrived smashed and i am returning it.
 
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Not exactly emissions (depite that's claimed officially), but fuel efficiency
(which results in reduced CO2 emissions as a direct correllation) by simply
reducing fluid drag (hotter oil is thinner). A secondary benefit is enhanced
= quicker evaporation of fuel and water contamination for extended oil life.

'Emissions' is today's most popular killer argument.
.
 
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Using the words 'powerful' and 'computer fans' in one single sentence is irritating me to say the least.



Ok 'computer' fan, was a poor choice of words, as noise is a factor with most every computer.

But good, I am glad you are irritated. Fester in it ! :0

This 12v 4.75"/120mm 'server' fan is rated at 254 CFM and has an impressive static pressure rating too.


It screams like a banshee @ 5400 rpm when fed 12vdc, and will chop off a fingertip, should one be so foolish as to let it.
It consumes About 45 [email protected] 12.6v.

There are some 92 and 80mm fans which can achieve 9600 and 12000 rpm respectively, and shoot a tight column of impressively high velocity air from them.

Here's a slightly larger( 5.2 inch) brushed motor 'radiator' fan which 'claims' 313 CFM. I've No experience with it, and likely never will.


The 254 cfm Delta fan, if placed face down and fed 12vdc, will levitate about 3/8" inch off the tabletop, then scurry right off the table. I employ several slightly less powerful versions that I power via a voltage bucker to nearly silent at ~ 5 volts and 0.11 amps, but can crank it upto 12.8v to screaming banshee and ~ 200 CFM and 2.10 amps consumption, at the flick of a wrist.

Most 120mm 'computer' fans top are generally in the 50 to 75cfm range, but can go as low as 19cfm at ~450 rpm, and as high as 260cfm at 5k+ rpm.

Sanyo San Ace has a 260 cfm 120Mm x38 mm fan which I believe is still the most powerful 120mm fan, that is perhaps still available.

Just don't call it a 'computer' fan, even though it looks nearly exactly the same as one to the untrained eye.
 
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This 12v 4.75"/120mm 'server' fan is rated at 254 CFM and has an impressive static pressure rating too.

Way too weak to yield a meaningful effect. Look for a Spal of at least 12",
better 15" diameter which will deliver ten to fifteen times the air volume
and also survive rain. As always use the proper gear for the application.
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