Found this on the web. Can't vouch for Mike the Mechanic, but he appears to knoiw a thing or two.

http://www.stylintrucks.com/Articles...ctric-fan.aspx

 

gots pics of mine on page 7......while idling in traffic i notice it kick on, but not too bad....i also have the wimpy alternator, you dont......since you run so cool anyways, i bet it would rarely ever kick on


https://dodgeforum.com/forum/2nd-gen...ric-fan-6.html

 

Damn, I did a search before I started this thread and NONE of those threads came up in the results. Thanks for the links.

 

With all due respect, that's the same argument that's used for electric fans on any site selling them as well. I don't buy the argument on price anymore. Last year, with the cafe standards, high price of metals, you're telling me that mass production of a plastic fan was significantly higher? Especially when every ad talks about how much h.p./mpg are there? Why wouldn't you try to make any improvement possible that didn't effect emissions?

Look, I'm not saying electric fans don't give some improvement, I question how much, and more importantly, I question the air flow quantities pushed by the aftermarket industry. Fans that say they pull "3300" cfm without any data to back up how it was certified. In hvac, they have fan curves, and they specify how much airflow a fan will move, vs how much resistance the fan has to fight.

Look at it like this, if you've ever taken a fan shroud off the radiator, it overheats...reason for this is you are physically changing the characteristics surrounding the fan, which changes what it can move. Factory fan might move 1500 cfm at idle utilizing the shroud, w/o the shroud maybe half that. It relies on the shroud to help create suction to move 1500. What drives me nuts is aftermarket says 3300 without saying how it's tested.

Again, I work in commercial hvac design, the furnace in your basement probably was rated to move 2,000 cfm, and can tell you the way the fan was certified was in a condition impossible to replicate in the field.


The reason I haven't gotten around to testing this is I want to do something thorough and come up with an electric fan set up that will cool these trucks for half of what anyone else is asking. All the aftermarket set ups seem to be asking for $250, I believe I can come up with a set up that will work just as well for under $100.

Know this is long winded, but wanted to make my point clear. I'm not saying electric fans don't work, I'm saying I believe benefits are over estimated, and after market is gouging you. I want to experiment with smaller fan styles properly placed so the electric amp draw, and sound, is not as significant as a '3300' cfm turbo prop.

I also want to do some number crunching on the effects of the current draw since it's significantly higher then, for instance, the small cars and suv's that have electric fans.

 

I don't think there's any dispute that an electric fan can cool a machine and more efficiently than an engine-driven fan. Look at the trucks and buggies that compete in SCORE and Baja events. Almost all use electric fans for cooling, and those vehicles run a lot hotter than anything most of us will see in our trucks. I agree that the electric fan industry is probaly its own worst enemy. There is no standardization and most are no better than snake oil salesmen with their pitches. That said, there are good sources of info on this and anyone doing the research can find them, obscure as they may be. There is no value for a fan maker to be deceptive. If a customer toasts a motor because of such deception then it is very likely many more people will hear about it. The internet is good that way.

I look forward to whatever you find out. I don't want to spend $500+ on a dual fan setup when I'm pretty sure the right single fan can do the same or better job as the stock fan.

 

efans work better than the stock setup. period. I've never gotten near the 210 mark with efans and used to see that regularly in the hot summer on the stocker.

I run a 16" puller and 14" pusher with no shroud. With a well designed shroud, I could probably get away with just the 16", but then my A/C would be as cold as it is with the 14" blowing straight into the condenser.

 

I agree with everything but good sources of information, because everything I've ever seen seems to be the standard saves money/more h.p that basically every aftermarket part claims.

All I was saying, and again I probably haven't don't a great job of explaining this, is I think people are getting ripped off by aftermarket. What I want to do is determine to what extent and be able to recommend the right alternative. Personally, I think the electric fan upgrade at $250-$500 is a rip off if you expect legitimate gains, but if you can do it for under $100, then why not because you're right, it's a better form of cooling.

As far as 'deceptive', it's not deception as much as fine print. I've never seen published fan performance information from any manufacturer, and have gotten no where when I did request it. My thinking is they are oversizing everything, which would not lead to having a liability issue since a motor wouldn't overheat. It happens all the time in commercial hvac where you can spend 100 times the amount you would for an auto fan. Why wouldn't it be happening here?

The word cfm is thrown around too much, and too few people understand it with fans. For example, the Mark 7 fan is highly sought after by people because it moves 'x' amount of cfm. What they don't understand is it only moves that amount of air in that particular installation. Once you move it from that exact space, it changes the fan characteristics and it no longer is moving that amount of airflow. I can promise you it's moving less air then it did in the Mark 7...yet it still works even though it isn't moving 'x' cfm anymore.

I just want to figure out exactly what the right airflow requirements are for our trucks, experiment with fans and installs until I find the right one. It'll take me an hour to measure the air flows, but really can't get into serious testing until it's August and 95 around here. Might spend weeks making sure it's the right one. Just don't want to say something off of calculations without blowing up my truck first if I'm wrong...lol.

Honestly probably won't help you, since everything I'll be doing is off my 5.9...wouldn't want to give you a suggestion without trying it for myself.

 

"Airflow-Cu. Ft./Min. at 0º Static Pressure"

This is what I'm talking about with the aftermarket, they advertise a fan running 2800 cfm at 0 static pressure. Most don't understand what 0 static pressure is, basically, nothing in front or behind the fan, no resistance or restriction. The second it's mounted up to the radiator, you have resistance, perhaps .2 static drop, fan performance is affected, and it's not moving 2800 cfm anymore. In commercial HVAC, they have a chart that you can calculate your performance, but the aftermarket fan industry doesn't do the same thing.

While I do believe electric fans are better alternatives for vehicles, just think people are getting ripped off and would like to research what's a great alternative for our trucks, that's cheap. Since the testing will be on a 5.9 4x4, I'd only recommend it for a similar vehicle with the 5.9 or 5.2, even 2wd since the cooling demands will be similar.

My hope is to say use 'x' fan for direct wire applications, use 'x' fan for thermostatic conditions, and having the costs be $60 to $100 new. I think it's nuts to spend $250-$500 for something that puts unnecessary load on the electrical system, but doesn't necessarily translate to better mpg or hp gains.

 

Well, technically they are correct, but the degree of which is the sticking point. What I'd like to see is a ROI calculation. At $500+ for a dual fan unit a .5-.75 mpg increase will never be paid back in gas savings and a 25 horsepower increase on this truck won't even be felt. If I can find a suitable fan in the $200 range that I can install myself, I'll do it. I'll let you know.

As for cfm being used as an objective judging criteria, I know all too well about that scam. As a technical writer/photographer in the motorcycle industry for 12 years I did a lot of product testing on the dyno. I used to laugh at some of the ridiculous claims made for a product that easily went down in flames once subjected to even minor scrutiny. The stories I could tell...

 

My issue with the h.p. performance gains is I feel they are ignoring the possible change to the charging system. Seen stories (and this is something I don't have a lot of knowledge in) that when the alternator is 'working' harder, it is harder to turn. If that's true, technically the electric fan would actually take away horsepower that is being saved by replacing the 'inefficient' fan. Think this is why the 'Up To' hp savings numbers are quoted. Also see why performance numbers could be different between a vehicle with a charging system with little demand, possibly a high amp alternator, and my vehicle, which isn't a premium amp alt and running a stereo system

No doubt the electric fan offers some savings, but like you said, if it's minimal, takes forever to pay off, then why bother? I'm not going to switch to electric fan for any h.p. or mpg changes, I just want the truck to warm up a bit faster. Anything else is bonus. Just want to do it cheaply and pay close attention to amp draw.