Check this out-nice little 2-speed fan harness...

[gmachinz]

Here's a unique 2-speed electric fan harness-rated @ 70 amps too! What do you guys think?

http://stores.homestead.com/hstrial-...lay/Detail.bok

[jhaymon]

$95.00!!!!! i think im in the wrong business . it would cost me 10 bux to build.

[HEI451]

Mine is also a whole lot less expensive, and a whole lot more efficient, it is called "dual groove pulleys, and, dual belts".

[jhaymon]

Originally Posted by HEI451

Mine is also a whole lot less expensive, and a whole lot more efficient, it is called "dual groove pulleys, and, dual belts".

yeah...we've proven that you dont lose HP by running a w/pump mounted fan fan. a million utube vids have proven it. all the speed and spike auto shop have proven it. e-fans are the myth that wont die

[panhandler62]

The primary reason the auto industry went to electric fans is because most newer cars have the engine mounted sideways. They also use e-fans in vehicles with the engines mounted front to back because it would be more expensive to manufacture multiple different cooling systems.

That said; there are applications where e-fans are superior performers, particularly when a vehicle spends a lot of time at idle as they are not dependent on engine speed or vehicle velocity.

What they will not do is give you an HP advantage. Converting torque to electricity and back to torque is inherently less efficient than transferring torque.

Most people make the conversion for style though anyway.

[HEI451]

Lets see, engine driven fans suck half the horsepower right out of an engine, right! Yeah...right. EVERYBODY says so, it's plastered all over the net, so, it MUST be absolutely true.

But, when an electric fan is used, all that horsepower comes right back, and, we benefit from them being for use with emissions engines that run at well over 200 degrees, some emissions engines those electric fans come off of, as high as 230 degrees. So, NO power loss at all from an over heated engine with the electric fans, along with reduced electrical charging system drag from the amperes the over worked alternator must produce to keep the horsepower sucking electric fam NOT being efficient.

Please, stop the hype of electric fans. I am a factory engine designer, have been for over two decades, and I KNOW BETTER, a lot better than to blindly believe that absolutely wrong, wrong, wrong electric fan sales hype and drivel.

The ONLY redeeming factor I saw in the first pictures by the original poster is, he managed to mount the fan inside the fan hole of the full radiator sized fan shroud, not the greatest setup, but the best (still mediocre) I have seen for a bad situation to date.

[panhandler62]

Why are you arguing when everyone is agreeing with you?

[HEI451]

I'm NOT arguing at all, I KNOW better than to fall for the electric fan con job, but, some just plain refuse to get the message. There are places for electric fans, designed for emissions engines that run at nuclear temps to reduce emissions, keep chamber temps up in aluminum engines that dissipate heat a lot faster and more efficiently than cast iron ones, and, our older engines that need completely different parameters to correctly cool at a lower temp.

Seems when someone else posts the con job they have read all over the net, it is blindly believed as gospel, but, when someone that knows the real truth posts it, he is lambasted as an idiot, as I was above, by jhayman. It seems that posting the real truth, the way it really works, just isn't what to do any more, as people just won't believe it, as opposed to the advertizing hype con job, the "gospel" according to sales departments.

Now, of course, he is fully welcome to his opinion, and nobody is trying to stop his voicing it, but, when someone else posts a dissenting one, from hands on experience, he shouldn't do any and everything to try to paint the other person as a moron about the topic, as he did towords me.

[panhandler62]

he is lambasted as an idiot, as I was above, by jhayman

I thought he was agreeing with you. perhaps I misunderstood him.

[HEI451]

Reread it, he wasn't agreeing with me, he was lambasting me because I had a dissenting opinion from his "educated from vendors on the net" information.

Anyone can go to numerous web boards and read where people have bought into the "electric fans make horsepower" myth, and read where an extremely small handful of the conversions worked, for some incredibly few individuals, and the myriad of the rest that now have more cooling problems than they imagined they ever had.

I have a 1991 Buick Park Avenue Ultra, nice car, EFI V6, needs paint, but, a great car. It has a stock electric fan, as the engine is mounted sideways in the chassis. It usually runs right at the 195 degrees the thermostat is rated at, IF the outsider temps are under 100 degrees/F. I took a trip to Carson City yesterday, left early afternoon, outside air temps were right at 106 deg/F. Car ran right at temp of thermostat when it was above 40 mph, but, ran as high as 235 deg/F under that speed, and traveling through suburban Cartoon City. Fan is just fine, sensors, tuning and engine are fine, cooling system is correct, fan/water pump/radiator cap work as they should.

I also have a 1986 GMC Safari van, EFI V6, factory 5 speed, single row radiator, stock engine driven fan, A/C fan clutch, 195 degree thermostat, per specification. It doesn't matter where or when it runs, or how fast, slow, it runs right at 195 degrees, idle, 10 mph, 40 mph, 100 mph.

I have a second small van, 1988 Chevy Astro van, same specs as the GMC, and it came to me with an electric fan in place, with the stock engine driven fan removed. Until I replaced the stock engine driven fan, fan shroud, A/C fan clutch back on the engine, engine would run 205 degrees above 40 mph, and 225 to 230 deg/F under that road speed, all day long.

I am in the process of finishing up the conversion to my 1964 C30 1 ton flatbed as well. It had a 292 in it, that had been run through the mill and blew the rear rod, because the PO just couldn't get it through his head it was a 50 mph truck, NOT an 80 mph vehicle. I replaced the I6 with a 305E V6 big block engine, same radiator as the 292, same fan, same fan pulley, no fan shroud, and am having a real time of it getting the thing to run up to the 175 degree thermostat. It simply doesn't want to run over 155 degrees. My next option is to carefully change the fan pulley diameter/drive ratio, slowing down the fan and water pump a few percentage points. (Maybe I should try an electric fan on the thing, that way, it'd probably run 230/235 degrees, and I wouldn't have to worry about it running too cold).

As I said, when I post something, I do it from hands on experience, and from being a factory engine design engineer for more than 3 minutes, I don't blindly formulate opinions and/or facts from hype con job sales ads and misinformation of others vested in sales.

It's as simple, and truthful as that.

[lyrikz]

Originally Posted by jhaymon

yeah...we've proven that you dont lose HP by running a w/pump mounted fan fan. a million utube vids have proven it. all the speed and spike auto shop have proven it. e-fans are the myth that wont die

Hold on what????????? Your saying that an engine driven fan does NOT rob horsepower??? THat is the only reason i went electric. lol.

[panhandler62]

Originally Posted by HEI451

Reread it, he wasn't agreeing with me, he was lambasting me because I had a dissenting opinion from his "educated from vendors on the net" information.

I guess I read it as sarcasm directed towards the "myth that won't die." Probably not worth pursuing, it's easy to mistake intent on message boards so unless he comes back and clarifies we have what we have.

Originally Posted by HEI451

Anyone can go to numerous web boards and read where people have bought into the "electric fans make horsepower" myth, and read where an extremely small handful of the conversions worked, for some incredibly few individuals, and the myriad of the rest that now have more cooling problems than they imagined they ever had.

Just on the face of it; I can't imagine how that could work unless it was critical to keep the engine coolant in a very narrow temperature range. That, of course, is something that electric fans can out perform mechanically driven fans at since they can be controlled independent of engine speed.

More generally speaking; I don't need a whole lot of data to know that converting rotational torque to electricity, storing it and then converting electricity back to rotational torque is less efficient than mechanically converting rotational torque to rotational torque.

People seem to think that electrical gadgetry runs free of mechanical cost which is just silly. No gizmo is going to free you from the laws of thermodynamics and they will inform you that any conversion of potential from one form to another has a net, irrecoverable, loss. In any given comparison, with equal fan design, you will lose efficiency with each conversion. A vastly more efficient fan design might save you more at that end than you loose in the conversion but you still loose in the conversion.

What you get with electric fans is aesthetics (looks modern, cool, shows off your chrome pulleys, etc.) and, if you set them up correctly, control. You do not get efficiency. The most efficient setup (presuming you need a fan because you run it more than a 1/4 mile at a time) is a properly sized and shrouded clutch fan.

There are any number of good arguments for running electric fans in a given vehicle but if it is a reduction in parasitic loss you are fishing for you are probably better served spending your money on other things.

[dwcsr]

Electric fans do reduce hp loss by not running nearly as much as a mechanical fan. Mechanical fans get their max CFM at max rpms as do electrics. Electrics can get their max rpm when the engine is at idle OR 6k rpm. Mechanical fans get their max rpm and max engine speed. Not efficient at all and not usually needed at 60 mph.

Converting mechanical to electrical energy is efficient if you know how DC motors work and is the main reason we don't use AC current in cars.
DC motors generate some of the power they use to run. ( I'm not going to explain why, look it up).

Electrics run 25% of the time a mechanical fan runs. You can't help but save HP loss.

All Fans need a shroud to work properly.

Keeping a tight engine temp is good for ALL engines not just aluminum blocks.

Most aftermarket fans are garbage and only sever to fix an ascetic issue where a big ass mechanical looks bad or won't fit.

Almost all aftermarket fan CFM specs are not close to advertised.

Most electrics are setup incorrectly to do any good. Slapping a 16" fan in the middle of the radiator and expecting it to cool is a waste of time and money.

OEM fans are designed to cool without regard to looks and do a good job when applied properly.

And the biggest internet myth on cooling..... Mark VIII fans put of 5000 to 5500 CFM.....NOT EVEN CLOSE.... 3200 max on high is a big wind.

[panhandler62]

You are tossing a lot of variables in there.

The most important thing to note is design. As you say, just slapping some aftermarket fan with skulls and what not in it's grill on the radiator is not going to accomplish much if you plan to do more with your truck than drag it around to shows on a trailer.

Where you note that electric fans run a smaller proportion of the time you have to consider design also. A mismatched electric may run more than a clutched mechanical does. Obviously; a fan bolted directly to the pulley runs constantly.

The only significant parasitic loss with a mechanical fan is air friction. The torque transfer to the water pump ins a constant in all setups so it doesn't figure into the equation. When you mount a fan on the water pump you add resistance from the air. If we assume similar blade efficiency then the equation boils down to z = a - (b + c ) where a is the energy required to turn the mechanical fan against resistance over a test period, b is the energy required to turn the electric fan(s) over a test period and c is the energy lost to entropy in converting rotational energy into electrical energy and then back to rotational energy.

Where z is negative the mechanical fan is better and where z is positive the electrical fan is better.

You might get lucky and save a small amount of parasitic loss by slapping in a set of fans you get off eBay but unless you sit down and carefully design a system; the best quick fix for cooling efficiency is to replace the hard mounted fan (if that is what you are looking at) with a clutched fan.

Of course; this entire discussion takes place in a very narrow savings window so your choices are probably better driven by aesthetics and clearance issues (and a lack of a motor mounted fan location at all on newer engines or after market serpentine kits.)

If the reason you are looking at fans is that you want more power you would get a lot more bang for you buck by dropping 4 or 5 bills on correctly tuned exhaust headers than a set of fans.

[VetteVet]

Originally Posted by gmachinz

Here's a unique 2-speed electric fan harness-rated @ 70 amps too! What do you guys think?

http://stores.homestead.com/hstrial-...lay/Detail.bok

I agree the harness is pricey but a 70 amp and a 50 amp relay is much more expensive than the 35 amp Bosch that most of us are familiar with, $7.00 at autozone. If you go to the website and click on "detailed description" it shows what's in the kit. If I was going to use a dual speed fan I would go to the local junkyard get one from one of the vehicles that used them and get the harness along with it. This includes the sender if it fits your engine.

As stated, either style will work on the older engines and it's mostly what style the owner likes. Virtually all the cars made in the nineties and later use the electric fans, even on the non-transverse mounted cars like the camaros and vettes. It's a shame that all the car manufacturers haven't heard about the high performance, high efficiency, mechanical belt driven fan.

[panhandler62]

Originally Posted by VetteVet

Virtually all the cars made in the nineties and later use the electric fans, even on the non-transverse mounted cars like the camaros and vettes.

Absolutely, but not as a means of improving performance. There are a variety of good reasons they use the electrics. The primary reasons are that emissions controls require very stable, somewhat higher, operating temperatures to function properly and it would be less economical to have less interchangeable systems and parts in manufacturing.

There may be any number of good reasons to run electrics but saving parasitic hp loss isn't a good one.

[HEI451]

I see LOTS of misinformation about the efficiency and application of electric fans here, all straight from the con job over hype advertizing and outright "don't really understand the way it really works, but" mantra.

Electric fans are NOT exponential in their operation, they are linear, temp hits one place on the sensor, fan goes on, another level, fan goes off. Electric fans do not have the ability to spin at different rpm levels in their operation, and are not specific for one temperature level. That is fact.

Engine driven fans, especially ones that use an air conditioning clutch fan, are exponential. The ones with a fan clutch, A/C or not, slip when the coolant is cool, tighten up as it heats, and, the fan clutch and fan, all of them, spin different rpm's with varying engine speeds (rpm"s). That is exponential, varying, not single speed linear.

And, a very narrow operating temperature band is essential for engine operating efficiency, too cold, or too hot, thermal efficiency, fuel economy, and drive-ability suffers greatly, engine component wear becomes excessive.

As I said, lots of the misinformation straight out of the con job hype from electric fan manufacturers here, way, way too much of it.

[VetteVet]

Originally Posted by panhandler62

Absolutely, but not as a means of improving performance. There are a variety of good reasons they use the electrics. The primary reasons are that emissions controls require very stable, somewhat higher, operating temperatures to function properly and it would be less economical to have less interchangeable systems and parts in manufacturing.

There may be any number of good reasons to run electrics but saving parasitic hp loss isn't a good one.

Pan you make good points but as DWSCR pointed out. The electric fans do not run all the time an thus there is no parasitic loss. Even with the inertial clutch there is drag on the engine and we are talking about overall operation being a HP increase and not a direct one for one ratio.

[panhandler62]

I think the larger issue is probably the way we too often do things. What looks cool is often the first criteria we lean on and too often we end up disappointed with the results.

I'll eventually have to choose which way to go with this. I'm not too worried right now because my front clip isn't even in the same building as my motor.

I'm not anti-electrics, just cautious that people might think it's an automatic change with no penalties. Dollar for dollar; the best you can possibly hope for (and are unlikely to realize) is 3 to 4 hp through reducing parasitic loss so if you focus is more power this probably isn't the best mod to spend money on.

If you are looking for better cooling a new copper finned radiator and the correct thermostat will probably yield better results.

If you are swapping to a serpentine system or dropping in an LS2 there probably isn't any place to even put a mechanical fan so it's a no-brainier in that case.

If you commute in stop and go traffic a couple of hours a day you might want to make the conversion to stay cool when idling in a crowd.

If you just think they look cool or wear your hair like Ted Nugent in 1981 and don't want to get caught in the fan those are valid reasons too, but if you just slap something in without some forethought and a bit of math; you might not like the results. As the price of that component in the OP suggests; moving to an electric fan setup can cost a few sheckles so I think the pros and cons should be carefully considered first.

We should also keep in mind that a fan that draws 20amps is using as much (or more) engine power as an AC compressor when it's running. I think some people do imagine that there is no draw on the engine when you use electric components. That's obviously wrong and it is information people should absorb.

[dwcsr]

Originally Posted by HEI451

Electric fans are NOT exponential in their operation, they are linear, temp hits one place on the sensor, fan goes on, another level, fan goes off. Electric fans do not have the ability to spin at different rpm levels in their operation, and are not specific for one temperature level. That is fact.

Your facts are incorrect. Ford has several Variable speed electric fans in their high end cars and spin up as needed for more cooling. There are several aftermarket kits that do the same. They even have a 2 speed fan that is very popular in the aftermarket

Originally Posted by HEI451

And, a very narrow operating temperature band is essential for engine operating efficiency, too cold, or too hot, thermal efficiency, fuel economy, and drive-ability suffers greatly, engine component wear becomes excessive.

As I said, lots of the misinformation straight out of the con job hype from electric fan manufacturers here, way, way too much of it.

I don't see anyone disagreeing with you on this the first time but you do tend to read in things not written.

[VetteVet]

Your facts are incorrect. Ford has several Variable speed electric fans in their high end cars and spin up as needed for more cooling. There are several aftermarket kits that do the same. They even have a 2 speed fan that is very popular in the aftermarket

Which is what this thread should have been about.

[dwcsr]

Originally Posted by VetteVet

Which is what this thread should have been about.

Really??, Since when do we ever stay on topic...... Mine is still bigger....

[VetteVet]

Originally Posted by dwcsr

Really??, Since when do we ever stay on topic...... Mine is still bigger....

[HEI451]

2 speeds are not exponential, they are...well, only 2 speeds. Still not enough to correctly cool an earlier non-emissions engine.

And, well, the single horsepower it takes to spin an engine driven fan, sooooo much loss of performance, gee, what a determent to a street driven vehicle.

All I was doing with the thermal efficiency was pointing out that it goes away with very narrow parameters of cool to hot.

I see a whole lot of electric fan con job hype advertizing talking points being posted here now, but not much practical and correct application. Keep getting that bogus info off them sales sites, I'll opt to keep getting my info from the engines myself.

[jhaymon]

..everyone calm down. i wasn't making fun of the product or anyone else. i was making a comment on the INTERNET set price of 2 relays, a few spade connectors, and 10' of wire.
i read most of these when i cooling down for the night. i can see how many are viewing and not talking. sometimes warning them it's a simple and relatively cheap setup that can picked up at any LOCAL parts store is just the right thing to do. and i was drinking.

hei.. "yeah" as in i do i agree.."blah blah"..as in i had a few beers in me.
i was agreeing with you. i only use e-fans when space is an issue or it's a parade-duty build. belts are much cheaper and much more reliable.

Hold on what????????? Your saying that an engine driven fan does NOT rob horsepower??? THat is the only reason i went electric. lol.

dont know if your being sarcastic or what. LOL is such a generic term these days.
if your serious, do what i did..pay the money for a few pulls on the dyno and find out yourself. I know they say seeing is believing, but i believe doing is the only way to really know for sure.