Electric fans on a pulling truck vs stock fan?

[Bobcat698]

I've seen quite a few pullers using electric fans on their Dodge trucks..

The question is, why? If you don't have an electric water pump to circulate coolant with the fans on but the truck off, why would it matter?

The fan doesn't kick on while going down the pulling track that I can tell, so why remove it, it is not really a parasitic drag on the pulleys if the clutch is not engaged, right?

Basically, I'm wondering why an electric fan/fans would be beneficial without an electric water pump.

Please clear this up for me, I'd appreciate it.

[getblown5.9]

i don't see the advantage, i dont think there is any HP gain worth noting when ditching the stock fan.

however for you automatic guys, an electric fan mounted on the tranny cooler would be a better idea for getting some nice airflow to keep the trans cooled down while idling and circulating the fluid

[dzlfarmboy]

Originally Posted by getblown5.9

i don't see the advantage, i dont think there is any HP gain worth noting when ditching the stock fan.

however for you automatic guys, an electric fan mounted on the tranny cooler would be a better idea for getting some nice airflow to keep the trans cooled down while idling and circulating the fluid

Yup this is going in place of my heat exchanger for the trans hooked up to a switch, should work fairly well.

http://www.derale.com/econo-cool.html

[Bobcat698]

Originally Posted by dzlfarmboy

Yup this is going in place of my heat exchanger for the trans hooked up to a switch, should work fairly well.

http://www.derale.com/econo-cool.html

You are taking the heat exchanger off the block then?

I plan on adding a cooler with fan on my tow rig.
What size are the stock trans fluid lines?

[zstroken]

Originally Posted by Bobcat698

I've seen quite a few pullers using electric fans on their Dodge trucks..

The question is, why? If you don't have an electric water pump to circulate coolant with the fans on but the truck off, why would it matter?

The fan doesn't kick on while going down the pulling track that I can tell, so why remove it, it is not really a parasitic drag on the pulleys if the clutch is not engaged, right?

Basically, I'm wondering why an electric fan/fans would be beneficial without an electric water pump.

Please clear this up for me, I'd appreciate it.

If it is a hot enough day the fan could come on. An option that would work jsut as well is finding an electric clutch. The horton clutch would work, or maybe adapt the 3rd gen fan to it. If the fan does come on, I think they say 25HP down the drain. Also while the truck is sitting idling, you can cool the truck even more with the electric fans. I think I played around, and if you hit 15 mph it would be equivalent to what the electric fans move in air flow. That might have been what I figured for a certain fan driven tranny cooler.

[dzlfarmboy]

Originally Posted by Bobcat698

You are taking the heat exchanger off the block then?

I plan on adding a cooler with fan on my tow rig.
What size are the stock trans fluid lines?

Their 1/2", Yeah cause im doing twins and it should work out alot better that way. When i can let it idle in Neutral and cool the trans after a hot run.

[Bobcat698]

What about something a little bigger, like this:
http://www.derale.com/atomic-cool.html

Let me know if you can get it already, I am a dealer for Derale if you need a hookup.

[kas83]

A mechanical, engine driven fan, will always draw some power. Although not locked up, it spins while the engine is running. It is a parasitic loss. And Garrett, you know the fan can do some damage when not even engaged if a finger/hand gets too close, having seen it.

Why do you think all the go-fast cars built now-a-days have electric fans instead of engine mounted fans? Rotating mass at higher rpms and drag are cons of the mechanical fan.

[DISTURBED]

I run electric fans between my radiator and intercooler(big Sperco) pulling air through the cooler and pushing through the radiator. the reason is to help my egt's i couldnt run water injection. with fan pulling through both my egt got way high so i moved them between the two and it acctually cooled it down my fans pull 5500 cfm.

[zstroken]

That being said I wander if just sealing the area between the radiator and intercooler would help. That way all air has to be drawn through the intercooler.

[DISTURBED]

I tried that and couldnt get it to seal very well hard to get all the way around so i moved radiator back 2 inches and the cooler forwards an inch to let the fans clear and i didnt have to do much to the grill to make it work.

[Muddin_dude06]

I have a question, how many CFM of air does the stock fan flow?

Garrett, I would think since your truck is a dedicated puller every little bit of drag you could reduce would net a gain. IMO you would be doing a good thing by upgrading to an electric fan/s.

[97' CTD]

It may sound stupid but it seems to take a slight load off the motor (Quick Reving). Not much but a hair, if I could keep my truck running for mor than a week at a time mabey I wouldent notice a difference.
Brandon

[kas83]

Stock fan on a Dodge truck is supposed to move 10,600 CFM, according to a shop that does mostly CTD's close by. The 5.9's were put in so many different configurations that it's hard to get a direct answer, but that's what I was told by the chief mechanic. Seemed to know his stuff.

[DISTURBED]

That sounds way to high if that were the case they would have to make the aftermarket fans do at least that to beable to keep the engine cool under heavy load. Flex-lite has one that does 6000 cfm's that is the biggest electric fans i have seen. are they saying 10,600 at highway speed or at dead stop and holding the motor wide open big difference.

[joefarmer]

If nothing else, e-fans are handy for front of the engine access. It takes 1/3 of the time to adjust timing, R&R a tach sensor, etc. It's also helpful for cooling the engine bay down after turning the truck off.

[BgBlDodge]

Flex-lite also recommends not towing very heavy loads when using their fans. I'd love to put a set of electric fans on my truck cause my stocker kills my mileage and power when it engages yet I'm not sure that the electric one's can keep the motor and tranny cool when it's 100* and I'm stuck in traffic with the AC on. Horton no longer makes the electric fan clutch for our trucks and even if they did I'm still not paying the $600 that they were charging for it.

Originally Posted by Flex-a-lite

Electric fans are not recommended for primary diesel engine cooling when the combined gross vehicle weight (CGVW) exceeds 18,000 pounds (truck, trailer and load)

http://www.flex-a-lite.com/auto/html/262-diesel.html

[kas83]

Originally Posted by DISTURBED

That sounds way to high if that were the case they would have to make the aftermarket fans do at least that to beable to keep the engine cool under heavy load. Flex-lite has one that does 6000 cfm's that is the biggest electric fans i have seen. are they saying 10,600 at highway speed or at dead stop and holding the motor wide open big difference.

Rated high idle no load speed, I would guess 3100 rpm since that's what they'll go stock. The stock fan also takes 27 hp to turn, according to him. Can you imagine a 27 hp electric motor, or twin 14's, right behind your radiator? The electrics will never keep up to a mechanical fan bolted to diesel. Semi's pull insane amounts of air with their fans at 1600 rpm, and they take approx 83 hp to turn, according to the shop manager at my last trucking company. There's a reason they still use huge, power robbing mechanical fans, electrics simply can't keep up.

[BowtiedCTD]

I run my electric fan cuz of limited space. and my fan is ALWAYS on while im pulling via toggle switch that overrides the temp engagement. I have a fan that pushes pulls 4100 CFM and it can keep my motor cool on a 80 degree day sitting still runnin for about a half hour where as without the electric fan it would boil over. i see the benefits when sitting and idling and the truck now never gets over 180* because of the electric fan. But i dont have an IC on my truck so its only pullin air through the radiator.

[NoSeeUm]

Originally Posted by DISTURBED

That sounds way to high if that were the case they would have to make the aftermarket fans do at least that to beable to keep the engine cool under heavy load. Flex-lite has one that does 6000 cfm's that is the biggest electric fans i have seen. are they saying 10,600 at highway speed or at dead stop and holding the motor wide open big difference.

Might be reasonable actually.

@ 10667 CFM and .38 psi D/P across the fan = 27 Hp

Jim