I have not crawled under to look, but from the top the only thing I see is a manual fan. So my question is.... Anyone done a conversion to electric? Thought it would be a easy way to gain a couple ponies and get better cooling at the same time.

 

I saw pictures posted of this

 

I found that post, but there was no direction on where it was purchased or the steps to install, looked to be custom. I would like to find a kit, that way I know it will cool the Hemi properly and install without having to fab anything.

The interesting thing in that post was he did a baseline dyno and an after and picked up 11 HP. I think that is extreme, I was thinking more like 5-7HP. It could possibly help gas milage a little as well.

I figure....

Cat back.... 5-8 HP Done
Ram Air 7-10 HP In progress
Fan 5-7 HP Winter project
Headers 10 HP Undecided if I want to do it


17-25 HP without headers, 27-35 with. All simple mods, well the ram air hood requires body work/painting ability, but the install is easy.

 

Are those estimates from a dyno? If not I would estimate they will total closer to 0 HP.

As far as the fan, how often is your fan on? Doesn't a clutch fan shut down at speed? Not much to be gained there.

 

No they are not from a dyno on my truck, just other results on other trucks. The clutch does reduce the drag on the engine, however the cluch is not always engaged.... The HP increase is not the only reason I am after the fan. When the fans are correct, they cool better ( when in traffic they cool the engine quicker), especially if air temps are high. Also opens the possibilty of running cooler, set the fans to kick on at lower temps and put in a cooler stat, although getting to hot is not really an issue on the Ram. I guess if you were to tow items in the heat it could be though. I did have a Firebird Formula and they always ran hot when you hit traffic. The Viper runs hot to, but Dodge recommends it on that car....

 

My personal opinion from going 'round and 'round about this on the Jeep sites is let the fan the Dodge engineers put in stay. You will never recoop the expense of the change, put a larger load on your electrical system which has to pull energy from somewhere, and if it was like the last conversion I did on my '86 Cherokee, a total PITA for no rewards other than a little quicker throttle response. The constant overheating soon overshadowed that gain. The only reason I would consider it is either on a rice burner that has a problem producing torque or a 4wd that sees a lot of action in deep water. With an electric fan you can install a kill switch for deep water crossings so your radiator does not get trashed.

 

In winter you can run without a fan,
see old post below:

----

Following up on the air dam on/off MPG tests I did on Monday the 23rd,
today I did a MPG test run at a cruise-controlled 70 mph over the same stretch
of Interstate 40 without my radiator fan.

I filled up at the same gas station, set the air conditioning the same, and
the weather was nearly the same - 70-79 degrees. Today there was a 10-15 mph
wind coming from the west (more on that later).

The truck was about 4 lbs heavier because I was carrying the big 1 7/16 inch
wrench, hammer, and small 1/2 inch flare wrench I used to remove the fan
bolts.

By the Exxon gas pump I used 11.105 gallons of 87 octane.
By my (corrected) truck's odometer I went 218.5 miles.

MPG at 70 mph without the radiator fan was 19.68
Compared to 18.94 MPG on Monday's test with fan,
this represents about a 3.8% gain.

The Oztrip meter results from measuring fuel injector on-time were similar,
showing a consumption of 11.6 gallons over 218.7 miles
for a fan-less mpg of 19.34
On Monday with the fan the Oztrip had showed 18.86 mpg, or a gain of 2.5%

When I first started this test run at about 10 am, the Oztrip meter showed
surprisingly good MPG - about 20 - so I had high hopes for what fan removal
was going to do.

Unfortunately, I found that part of the gain on the southeast bound leg of the
trip was due to the 10-15 mph winds at my back.

When I turned around at Wilmington NC and headed back, the average mpg
steadily dropped as I now drove against a head wind. Looking at the Oztrip
trip computer numbers it seems I averaged 19.96 on the southeast bound drive
with the favorable tailwind, and 18.7 driving northwest with the unfavorable
headwind. This was the 1st time I had bothered to watch for what winds do to
mpg. Looks like they can raise/lower mpg by 1.6 even at a "calm" 10-15 mph
level.

As to the temperature of the coolant without the fan - it stayed very steady
at 180 degrees during the MPG test run even with the air conditioner on.

When I slowed to a stop at the end of the trip while turning back into the gas
station, the temp gauge indicated a momentary rise to about 195.

I actually took the fan off late yesterday afternoon and drove around without
it to experiment. As long as the truck kept moving the temp gauge stayed at
180. I parked the truck and let it idle for about 10 minutes. This raised
the temp gauge to about 210-220. I then put on the heater full blast to see
if this would lower the temperature back to 180. It did not - the temp stayed
the same and neither fell nor raised any more. I then drove the truck again.
Within 1 mile the temp had dropped to 200 and within another mile it was back
at 180 degrees F.

The fan on a 5.9V8 Magnum is kind of funky looking. It has 5 blades, but 2 of
them are bunched together and the other 3 are spaced out normally. There is a
stiffening wire embedded in the blades. It takes less than 15 minutes to take
this fan off, but if the fan had been made in two parts that split - you would
not have to take the big nut off the fan clutch - and the fan could be removed
in 5 minutes.

Instead of buying a 36 mm wrench {1.417 inches}, I cut two strips of metal
from a tin can. These strips turned out to be 0.010 inches thick. I taped
two such home-made 'shims' to the inside faces of my 1 7/16 wrench {1.4375}
which closed the opening up to 1.4375 - 0.020 = 1.4175 This worked fine to
loosen the clutch-to-waterpump nut. Make the shims 'fish hook' shaped and you
can tape them in place from the backside. 3M 'super strong' Exterior double sided mounting tape works well for this.

I still have the Evan Cooling 'waterless' NPG coolant in my engine. This
won't boil over until 370 degrees so I have some safety factor that a normal
antifreeze would not have.

>Hank,
>I found better results when I installed the electric fan on my Dakota. Mag
>whereas you have the 5.9. My fan is of different configuration that yours
too. >Instead of the 7 blade fan you have, or the 5 blade fan shown in the
Dodge >ad's. I have a monstrous fan with 9 equally spaced blades. It must
weigh 15 >lbs including the clutch. My mileage went from 14.8 to 16.4, not
cruise >controlled, My highway mileage change equates to a 9.2% increase
without >the fan. John

John,
It makes sense to me that a Dakota might have a bigger gain from not using the
fan.

If a Ram uses 60-70 horsepower to cruise at 70 mph, a smaller, lighter Dakota
might use only 45-55 hp. Since the fan wastes about the same same in either
case, the Dakota mpg would go up more.

It is interesting to hear of your bigger 9 blade/heavy fan. Would this be a
'towing package' option that we have not noticed before ?

How much horsepower does the stock fan waste ?
Here's a ballpark guess -

The gaspump said I saved .425 gallons.
The Oztrip meter said I saved .28 gal
The average is .35 gallons.

This .35 gallons was saved over about a 3.1 hour trip,
or about .35/3.1 = .11 gallons per hour.

A gallon of Exxon 87 octane weighs 6.16 lbs per gallon.
So I saved .11 gal x 6.16 lbs/gal = .70 lbs gasoline per hour

A rough rule of thumb is that on average a engine will use between 0.40 and
0.65 pounds of gasoline for each horsepower that is generates per hour it
runs. This is called by engineers the "Brake Specific Fuel Consumption", or
BSFC.

Picking 0.55 lbs fuel/hp-hr as a part-throttle average -

.70 lbs fuel/hr divided by 0.55 lbs fuel/hp-hr = 1.2 horsepower
for the viscous clutch mounted fan,
which is supposed to spin at around 800 rpm maximum
when not engaged by the 220 deg F clutch bimetallic coil to 'lock' and turn at engine rpm.

 

That is a really smart calculation.

 

The electric fan won't do much at the cool end of the operating range, because like you say, the stat is going to control that. I wouldn't recommend a cooler stat unless you can reprogram your computer. I put a 180 on my 454 motorhome (replacing a 195) thinking cooler was better, which was true back in the day with carbs and no computers.

Now what happens is with the cooler stat, it never gets to the "normal" temp the computer is looking for so the computer thinks it's still warming up and runs the mixture rich and never goes into closed loop. I ended up fouling an O2 sensor and flunking an emissions test. If you can reprogram the computer to go to closed loop at the lower temp, that would solve that. I don't know if that would cause other issues though.

A little off the original issue of the merits of the electric fan, but something to note.

 

hey whats up guys....So today i just finished up my install of Flex-a-lite's black magic 16" electric fan kit. Simple install...great product. simply put. Ive done some test driving and it does a great job. The fan came with a adjustable thermo...If you do end up getting one I suggest leaving the thermo at the lowest setting (160-240). even though the thermostat on the truck opens at 180....i just think its a good idea to keep the truck cool as much as possible. especially for town style driving...I bought my kit at napa auto parts....with tax it was about $245...way good deal! other places wanted around 300$...The engine deffinatly some gained power (maybe 10hp)...very noticible when getting on the highway. although i do have a air intake and a 40 series flow. Piont is...get an electric fan...it only benifits your truck.