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electric fan increasing gas mileage?

  • Thread starter Thread starter Bad92GT
  • Start date Start date Jun 5, 2006

Bad92GT

The 5 Minute Plan Man
Jun 10, 2004
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Jun 5, 2006
#1
  • Jun 5, 2006
  • #1
not sure if its correct or not but the guys on Horsepower TV said they could see an addition to the MPG because of freeing up the motor.. i doubt it.. just wondering if its true
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
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#2
  • Jun 5, 2006
  • #2
In theory, you bet. In the real world, there are a ton of factors. But even if the milage increase is slight, a 1 MPG increase (for example) is great.
 

Vinnietbird

Member
Jun 2, 2005
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#3
  • Jun 5, 2006
  • #3
I'd be happy with a 1 mpg increase.I still have 2 Taurus fans in the garage.I need to get one on,but I'm not quite sure how to wire it yet.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jun 5, 2006
#4
  • Jun 5, 2006
  • #4
For simplicity and optimal function, see Dc Control for a controller.

Otherwise, we can help ya wire something up.
 

90mustangGT

I felt sorry for girls because
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#5
  • Jun 5, 2006
  • #5
The reason for the swap to electric fans from the factory was for a gas milege difference. In reality, electric fans are more reliable than clutch fans, however, when a clutch fan goes bad, it either gets weak, or just seizes up, which the vehicle will operate and still cool for a while, but an electric fan either works, or it doesn't.
 
C

clarkjr

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#6
  • Jun 5, 2006
  • #6
Remember that there is no free lunch. When the EL fan runs, the alt works harder and thus creates more drag. May depend on what type of driving you do. Mainly HWY, the EL fan would not need to run where as the mech fan would always run there so it would help MPG. Mostly town driving, may not help MPG.
 

srothfuss

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Jun 5, 2006
#7
  • Jun 5, 2006
  • #7
most benifits from the electric fan are seen on the highway. Since your car (any car) is traveling fast enough for air to pass through the radiator on it's own the fan can turn itself off... That way there is no additional load on the alternator and you save run time on the fan motor.

In town or traffic, I haven't picked up any MPG yet, but that is probably because of my right foot recently
 

Darkwriter77

Resident Ranting Negative Nancy
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Jun 6, 2006
#8
  • Jun 6, 2006
  • #8
The amperage draw issue is negated if you install a higher-output alternator (3g OEM 130amp unit or something larger). The electrical draw on the alternator is not going to pull nearly as much HP from the system as a mechanical clutch fan. The biggest gain is in the higher RPM's, of course, but even at idle and just tooling around, you can feel a difference when you ditch the stock fan. Cuts down a ton of engine noise, too.
 

jrichker

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#9
  • Jun 6, 2006
  • #9
The electric fan pulls about 1/2 HP of electrical power. Using 746 watts = 1 HP, then 14 volts x 30 amps = 430 watts /746 = .56 HP.

The stock fan pulls 5-12 HP depending on who you ask. Any way you cut it , the electric fan frees up some HP, and can possibly increase gas mileage.
 
S

Sicarius428

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Jan 6, 2004
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Jun 6, 2006
#10
  • Jun 6, 2006
  • #10
It might but I didn't notice a difference in MPG. My engine revs more freely though.
Kevin
 

CanadaStang

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#11
  • Jun 6, 2006
  • #11
srothfuss said:
most benifits from the electric fan are seen on the highway. Since your car (any car) is traveling fast enough for air to pass through the radiator on it's own the fan can turn itself off... That way there is no additional load on the alternator and you save run time on the fan motor.
Click to expand...
What he said ^^
I never really noticed any measurable difference in MPG with my 91 LX after the fan install but without back to back tests on the same day with same conditions, it's difficult to really compare actual MPG
 

Vinnietbird

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#12
  • Jun 6, 2006
  • #12
When I take a week off this summer,I'll be asking questions for the details of the install.
 
M

macx

New Member
Jul 18, 2004
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Jun 6, 2006
#13
  • Jun 6, 2006
  • #13
jrichker said:
The electric fan pulls about 1/2 HP of electrical power. Using 746 watts = 1 HP, then 14 volts x 30 amps = 430 watts /746 = .56 HP.

The stock fan pulls 5-12 HP depending on who you ask. Any way you cut it , the electric fan frees up some HP, and can possibly increase gas mileage.
Click to expand...

I've read similar info.

I noticed 1-1/2 to 2 mpg overall increase, mixed driving.
Fan doesn't run at all on the highway, or really as long as
I'm moving even 20 mph.

Taurus fan (4.2 motor 2 speed version)

Flex A Lite variable speed soft start controller

Had it on my 351 for a year, works absolutely great, no cooling
probl's at all, even in 90's weather, stopped at lights, idling in gear.
I've got an LED wired in the dash to tell me when the fan's running,
and at stop lites it'll come on for a very brief time and shut back off.
I've got a 3 core brass radiator, hi-flow 180 T stat, and a Weiand
hp pump, so the whole system has good cooling capacity.

It delays starting the fan for a few seconds when you turn the key
to start the engine, that way it doesn't draw to start the fan at the
same time you're using the starter.

You can also easily hook up switches for manual on or off.

When it does start, it runs at like 60% until/if the coolant
temp continues to get hotter, then it automatically speeds
up the fan as needed, all the way up to 100% if necessary.


I've got my control set for about 185. As soon as it kicks on, the
temp starts to decrease.

With the FAL control no relays needed, I believe it's a little cheaper
than a DC setup. $100 on Summit, you need the bigger of the 2
on there for a 4.2 Taurus fan. Real easy to wire.

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

And I got SUPERB customer service w/questions etc from FAL.
 

Look Its Aaron

Your car looks like it came straight from Mexico.
Founding Member
Nov 18, 2001
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Jun 7, 2006
#14
  • Jun 7, 2006
  • #14
Still have not got around to installing an e-fan. Soon though.
 
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