Efan conversion for cold climate

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Fangt

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I have been reading up lots on Efan conversion on 5.7 hemi, seems to be fairly easy to do.
I really like the clean look if V6 Efan and quieter operation.
Just have a few questions on it specially for cold Canadian climate before I pull the plug.
1. Have anyone did the Efan conversion see any noticeable gain in torque and fuel mileage?
2. Where I live, the temperature can go down to -40C/-40F in the morning. When I start my truck in the morning, the mechanical fan always comes on for a minutes or two. I was told it is normal regardless of the starting temperature, because it increase the engine load to bring up the oil temperature quicker. Is this true? If it is, will a Efan conversion have negative impact on cold start?
3. Is a lower temperature thermostat and tuner really necessary for this conversion? Since Efan is controlled by AC, if I do not run AC, it will not be running, therefore only cooling is from natural air flow right? I do tow about 9000LB for long road trip through the Rocky mountains in summer time, does this mean I need to keep AC on all the time when I am towing? If I do, whatever torque/fuel mileage gain will be offset by AC compressor, right? if I do not turn AC on, at what temperature will the Efan kick in without tuner and with stock thermostat?
4. I noticed that my mechanical fan is always running regardless of coolant temperature. Just at different speed, higher speed at start up and slow down afterword. Does that mean the fan clutch is faulty?
Thanks.
 

pacofortacos

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My experience on my 2016.
1. Minimal torque gain, no mpg gain

2. Clutch fan comes on cold because the fluid in it has to thin out a bit for it to slip. Doesn't heat the oil in the engine more as it starts to slip within a minute or so. No neg. impact

3.Lower thermostat and tune are not mandatory but can help. Stock will turn on the fan @ 221 deg. or so. Removing a few of the shutters will help keep the temp down if you don't have a tune - just removing from the top, rows 2 and 3 shutters will keep the temps more stable when moving.
Truck is more mpg efficient with AC on and windows shut vs. windows open - in theory.

4.Your clutch fan is working normally and actually is pretty efficient.
 
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Fangt

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Thank you. You sir is a gentlemen and a scholar.
 

Wild one

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I have been reading up lots on Efan conversion on 5.7 hemi, seems to be fairly easy to do.
I really like the clean look if V6 Efan and quieter operation.
Just have a few questions on it specially for cold Canadian climate before I pull the plug.
1. Have anyone did the Efan conversion see any noticeable gain in torque and fuel mileage?
2. Where I live, the temperature can go down to -40C/-40F in the morning. When I start my truck in the morning, the mechanical fan always comes on for a minutes or two. I was told it is normal regardless of the starting temperature, because it increase the engine load to bring up the oil temperature quicker. Is this true? If it is, will a Efan conversion have negative impact on cold start?
3. Is a lower temperature thermostat and tuner really necessary for this conversion? Since Efan is controlled by AC, if I do not run AC, it will not be running, therefore only cooling is from natural air flow right? I do tow about 9000LB for long road trip through the Rocky mountains in summer time, does this mean I need to keep AC on all the time when I am towing? If I do, whatever torque/fuel mileage gain will be offset by AC compressor, right? if I do not turn AC on, at what temperature will the Efan kick in without tuner and with stock thermostat?
4. I noticed that my mechanical fan is always running regardless of coolant temperature. Just at different speed, higher speed at start up and slow down afterword. Does that mean the fan clutch is faulty?
Thanks.

If you're towing in your case you'd want to be tuned so the e-fan comes on a bit earlier. It won't kick in till roughly 220F if the On/Off parameters aren't reset. If you don't want to tune it,you'd be better off leaving it stock
 

pacofortacos

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Since the OP has a 2014 at least he can tune it for a very reasonable cost - even if his tune is just the stock tune with updated efan parameters.
 
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Fangt

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After much consideration, I decided to not go with Efan conversation. The V6 Efan cost about 170 and Diablo Predator 2 tuner cost about 500. It is hard to justify that amount of money for marginal gain in torque....
Thank you all for your suggestions.
 

crash68

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I do tow about 9000LB for long road trip through the Rocky mountains in summer time, does this mean I need to keep AC on all the time when I am towing?

You might need a more powerful electric fan or stick with the mechanical clutch fan for being able to cool the engine under big loads/towing.
One of shortcomings of the Gen2 EcoDiesel is the lack of a mechanical fan. Granted it has a considerably larger electric fan(850 watt/70 amp) that what your considering to run, it's not capable of moving as much as a mechanical. The EcoDiesel also has a higher fin density radiator than the Hemi.
The road block to using this fan on the Hemi is how to control it, it uses just a PWM signal from the PCM to drive the speed.
 

pacofortacos

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After much consideration, I decided to not go with Efan conversation. The V6 Efan cost about 170 and Diablo Predator 2 tuner cost about 500. It is hard to justify that amount of money for marginal gain in torque....
Thank you all for your suggestions.

Your 2014 should have an efan on it stock.
If you want to see the difference, just take off your clutch fan (leave the shroud on, just remove the fan) and drive around for a bit.
I have towed with just the stock efan and no clutch, but not over the Rockies.

You can remove and install the clutch fan without taking anything else apart - at least I can on my 2016. It's a bit tight to get in and out but it is possible. Once loose it literally take 5-10 minutes to remove it.

Also if you want to keep the temps from moving around so much, just remove 2 to 3 of the top 4 rows of the shutters - you have to leave the top row in. It will get warm sitting still (but even 220 isn't that hot, it is the designed temp before the shutters will open and fan kicks on), but as soon as you start moving the temp will drop down to the low 200's with a 203 deg. stock thermostat.

It's all free :)

AS far as I could tell, the stock efan with stock shroud installed, cooled as well as the 3.7 V6 fan when I tested it. Both OEM fans, not aftermarket.
 
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Fangt

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It appears the shape of stock shroud on V8 is better at directing air flow toward the engine than shroud of V6 Efan, so it make sense that it can cool the engine as well as V6 Efan, even being a little smaller than V6 Efan. On that note, anyone tried the combination of V6 Efan itself with V8 shroud? That combination will cool the engine down fast, I'd guess. I have heard the V6 Efan is integrated into the shroud, but the ingenuity of our members can be very surprising. lol.
I am fairly sure the stock Efan without the fan clutch will work in most situations, at least up here, where the hottest day in summer is about 35C/95F and does not last long.
Problem with removing a couple of shutters is the engine temperature will come up slower for those bitter cold winter mornings.
What confuses me is that the stock mechanical fan turns on when I start the truck in cold -35C/-31F morning.....I know the shutters are closed but it will still cool down the engine to some degree when the engine needs to warm up. Maybe just inherent flaw of the viscous clutch. When the fluid is so cold that it reach such a high viscosity, it will lock up the fan without moving away from the center of the clutch? Maybe removing mechanical fan is actually beneficial in this situation?
Just tossing out ideas.....
 
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Fangt

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There is how the fan clutch works. I have not taken mine out yet, I just assumed that the ones in V8 engine is fluid coupling clutch...
 

pacofortacos

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The V6 fan won't fit with the stock shroud, you would have to destroy the V6 shroud and that defeats the main purpose of going to it - which is more room in the engine bay.
The fan itself is only a couple of inches larger than the stock fan.

Removing a row or 2 of shutters might slow down warm up, but to honest that's really the thermostats job. Ideally there's little to no coolant going through the radiator until after the thermostat opens.
But it would let a little more air flow over the motor itself.

The shutters also do not cover the entire radiator, the bottom 1/3 or so is wide open.
Yes the clutch fan moves air across the radiator even with all of the shutters closed - the bottom is open and it isn't air tight to begin with.
Even when slipping, the fan still moves a decent amount of air. But nothing close to what it moves when engaged!
 
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Fangt

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Good points. I did learn a lots from this thread.
 

clint440

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The throttle response is better without the clutch fan. I noticed it when I had it off and on and back off. Dorman sells a nice 3.7 V6 fan at a reasonable price. You could always experiment yourself, the AC fan will keep the engine cool, it just cycles on an off more without the shroud.
 
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Fangt

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My understanding is that Efan conversion without low temperature thermostat, and tuner will give better throttle response and will work in most normal driving conditions. Stock V8 fans will work better when do heavy towing....unless if I invest in a tuner and low temperature thermostat.
If my understanding is correct. I will get a pedal commander which will give more choices on throttle response with half or third of the cost and still retain the cooling capacity of stock setup for heavy towing.
Of course, this is all based on the climate I am in. Mild summer and so cold in winter that it can freeze the balls off a brass monkey.
 
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pacofortacos

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What are you trying to accomplish.
I don't get the pedal commander thing - but I don't have one either.

My understanding is that is just opens the throttle faster than the pcm does after the pcm learns most peoples driving habits. You could always just mash the gas pedal down farther and faster and I think it is the same basic thing.

It's a feeling thing vs. any real power increase. At least with a tuner it's possible to get more power - usually requires better gas but it's possible with 87 octane to gain at least a bit.

You can often find a used tuner for sale, just make sure it is unmarried.
 
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Fangt

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The original post was trying to find the pros and cons of V6 Efan conversion on V8 hemi for my particular climate (extrem cold in winter and mild summer) and application (heavy towing up and down mountains in summer). It seems the saving on torque and MPG does not really justify the conversion, to do it properly that is (V6 Efan, lower temp. thermostat and tuner), at least to me.
Throttle response is not as important to me as torque and fuel milage, if I want to let her rip, I can just step on it a little harder.
It got a little side tracked like most of post are. Lol.
Sorry for the confusion.
 

Daw14

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When towing,I prefer having an extra fan, if your electric ***** the bed you still have a backup.
 

MikeSumthin

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I simply just removed the clutch fan and shroud and use the stock Efan.

Tuned it using a $300 Diablo i3 that I already had.

Purpose was to take stress off the water pump and give more room in the engine bay to work.

Taking off parasitic drag, weight reduction, and eliminating the loud whirling noise at startup are just bonuses.

Sent from my SM-G988U1 using Tapatalk
 
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