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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Clutch Fan vs Flex Fan

  • Thread starter Thread starter larrendeuce
  • Start date Start date May 6, 2004

larrendeuce

Member
Sep 13, 2003
649
1
19
Southern NJ
May 6, 2004
#1
  • May 6, 2004
  • #1
I've been looking into the performance differences between the stock clutch fan and a flex fan. I haven't seen any hard numbers though. Some say the clutch is better because the fan can disengage. The Flex fan is lighter. I want to know because my car came with a flex fan when I bought it. I just got a free clutch fan from a friend. I'm going to the track soon to see how it affects 1/4 mile times unless someone else want to contribute.
 

hllon4whls

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Founding Member
Jan 17, 2002
2,567
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46
Covington
May 6, 2004
#2
  • May 6, 2004
  • #2
Flex fans tend to be noisy, but light with a lot of air flow. They are not the friendliest on hp either. The OEM fan is very heavy, but the clutch allows it to slip and help on hp loss.
 

larrendeuce

Member
Sep 13, 2003
649
1
19
Southern NJ
May 6, 2004
#3
  • May 6, 2004
  • #3
Yeah the flex fan is really loud. I can hear it over my exhaust.
 

_jb_

New Member
Mar 4, 2004
808
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0
Michigan, Berrien County
May 6, 2004
#4
  • May 6, 2004
  • #4
My flex fan isn't loud. The electric fan I was going to put in makes a lot more noise, and my clutch fan was shot. So for about $40 I got a new fan and works fine...unless your car starts to overheat because you got the wrong rotation fan lol! Just happened to me. Put a big new 3 Core radiator in and it was still getting hot. Then my dad's cigarette smoke was being blown away from the car and it dawned on us lol. I guess smoking has an advantage...but still wish he didn't do it.
 

drgn5.0

Founding Member
Mar 13, 2001
603
0
0
May 6, 2004
#5
  • May 6, 2004
  • #5
you need to get an exhaust if you can hear the flex fan over it.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 7, 2004
#6
  • May 7, 2004
  • #6
my take: fan clutches are kinda finicky. they have to be stored properly, etc. and they lose a few hundred RPM every year (if not more). if there is any silicone around the thermo-spring, it is bad.

since you are askin about performance oriented stuff with the fans......i would consider an electric fan. should you need a new clutch after all, the 3G upgrade and a J/Y fan are not that far away cost wise (esp if this is something you were gonna do later). a good HD clutch will set you back nearly a hundred bucks if you end up needing one.....
im just tossing out stuff to think about. i renewed my stock set up, cuz i dont have a 3G and i need a lot of flow - temps are 90*+ 6-9 months of the year here. so the stock fan set up delivers, when fresh. but i still think that perhaps i should have just spent some more $$ and done the electrical upgrades. good luck.
 
B

blk92stangg

New Member
Jan 30, 2004
583
0
0
Hawaii
May 7, 2004
#7
  • May 7, 2004
  • #7
I got away cheap with my 65 buck fan clutch then LOL. Hope it lasts a little while. I would guess that the difference between the 2 would be negligible. Maybe the flex fan would give up a little down low, before the blades flatten out from centripedal force and contribute a little more drag.
 
S

shorty1993

New Member
Apr 16, 2004
212
1
0
Gadsden, AL
May 7, 2004
#8
  • May 7, 2004
  • #8
since on the subject i found a good deal on a black magic fan, i know i have heard a few bad and few good things about these. but am planning on going with a good aluminum radiator soon, so thought with that set up it may run cool enough. also fixing to put a new chain set on along with a high volume water pump. any thoughts on that.
 

larrendeuce

Member
Sep 13, 2003
649
1
19
Southern NJ
May 7, 2004
#9
  • May 7, 2004
  • #9
I'll dig up this thread and post times after I get to the track tuesday.
 

patdow1

New Member
Mar 1, 2003
201
0
0
Murrieta CA
May 7, 2004
#10
  • May 7, 2004
  • #10
I was in your delima before I decided to go with a electric fan. I for one can vouch that the "Black Magic" Electric fan is noisy as hell with bells on. People always stop me to tell me "Hey your car is still on" as I'm getting out of the car But as far as cooling it works just fine it's just noisy. Temp needle never sees past 1st line above 135* As sig says I also have a Griffin Aluminum Radiator as well which helps.
 

Legendary

Founding Member
Oct 10, 2002
1,925
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0
City of Angels
May 7, 2004
#11
  • May 7, 2004
  • #11
My car seemed to rev easier with the flex fan and out of the 2-3 years I had it I never had a problem or had to replace anything. It wasn't loud and with the undrive pulleys I couldn't hear it at all. Good fan imo. I like my electric better though
 
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