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Flex fan or fan clutch??? Which to use?????? #103287 08/11/08 05:15 PM 08/11/08 05:15 PM
Joined: Mar 2004 Posts: 1,365 So Cal GoManGo70Bee OP super street
GoManGo70Bee OP super street Joined: Mar 2004 Posts: 1,365 So Cal	What are the ups and downs to both? Which work better? Thanks!! 70 Superbee 383 4 speed 70 Hurst 300 67 Dart sedan 74 Ramcharger 03 Hemi Ram 1500 4X4

Re: Flex fan or fan clutch??? Which to use?????? [Re: GoManGo70Bee] #103288 08/11/08 06:09 PM 08/11/08 06:09 PM
Joined: Feb 2003 Posts: 21,318 Manitoba, Canada DaytonaTurbo Too Many Posts
DaytonaTurbo Too Many Posts Joined: Feb 2003 Posts: 21,318 Manitoba, Canada	I like the clutch fans. Have heard too many horror stories about the flex units.

Re: Flex fan or fan clutch??? Which to use?????? [Re: DaytonaTurbo] #103289 08/11/08 06:18 PM 08/11/08 06:18 PM
Joined: Jan 2007 Posts: 7,664 IN A ahy master
ahy master A Joined: Jan 2007 Posts: 7,664 IN	I believe (thermal) clutch fans can move more air when its needed and rob less power when lots of air isn't needed. Also proven and reliable. Available used and new. I put the 5 blade MP clutch/fan unit (Mancini) on a 493 B engine and it works great even with AC. With any fan a correct fitting shroud is a must for cooling at idle and low speeds.

Re: Flex fan or fan clutch??? Which to use?????? [Re: ahy] #103290 08/11/08 06:26 PM 08/11/08 06:26 PM
Joined: Mar 2005 Posts: 1,373 Rancho Cucamonga, CA D_C pro stock
D_C pro stock Joined: Mar 2005 Posts: 1,373 Rancho Cucamonga, CA	Flex Fans are cheap and move air, but can self-destruct and always rob power (even though less when they flatten-out at high-RPM, they still waste more.) Clutch-Fans improve fuel-economy and performance. They were standard-equipment on Performance and A/C equipped vehicles from the factory. I switched over 8-years ago. High-flow Electric Water-pumps and Fans, plus Aluminum radiators are better still, but non-original and more expensive.

Re: Flex fan or fan clutch??? Which to use?????? [Re: ahy] #103291 08/11/08 06:27 PM 08/11/08 06:27 PM
Joined: Mar 2004 Posts: 1,365 So Cal GoManGo70Bee OP super street
GoManGo70Bee OP super street Joined: Mar 2004 Posts: 1,365 So Cal	Quote: I believe (thermal) clutch fans can move more air when its needed and rob less power when lots of air isn't needed. Also proven and reliable. Available used and new. I put the 5 blade MP clutch/fan unit (Mancini) on a 493 B engine and it works great even with AC. With any fan a correct fitting shroud is a must for cooling at idle and low speeds. Do you know the diameter of the MP fan? 70 Superbee 383 4 speed 70 Hurst 300 67 Dart sedan 74 Ramcharger 03 Hemi Ram 1500 4X4

Re: Flex fan or fan clutch??? Which to use?????? [Re: GoManGo70Bee] #103292 08/11/08 06:28 PM 08/11/08 06:28 PM
Joined: Dec 2007 Posts: 18,160 Mass DAYCLONA I Live Here
DAYCLONA I Live Here Joined: Dec 2007 Posts: 18,160 Mass	Quote: What are the ups and downs to both? Which work better? Thanks!! Neither,,,,,,use a fixed 5 or 7 blade factory fan,....it's not like that 5 HP loss is gonna be noticed........but 200+ degrees F....will And be sure to use a full shroud...... 4612409-0000a.jpg (50 downloads)

Re: Flex fan or fan clutch??? Which to use?????? [Re: ahy] #103293 08/11/08 06:35 PM 08/11/08 06:35 PM
Joined: Nov 2004 Posts: 5,118 Alone in the darkness gamagoat6x6 super street
gamagoat6x6 super street Joined: Nov 2004 Posts: 5,118 Alone in the darkness	Everything I own has a big 7 blade thermal clutch fan and if I get a car that doesn`t it gets one soon. A big one will move more air than anything else when required or just go along for the ride when it isn`t needed using almost zero power. Best of both worlds and they`re quiet when disengaged. Why didn`t everything get `em from the factory? because they`re expensive to produce so they were reserved for things that really needed good cooling like top of the line heavily optioned cars and HD trucks. If it`s good enough to cool this hard workin` beast it`s sure good enough for a car application. `02 RAM2500 SPORT V10 4x4 `06 GMC sierra NO cars

Re: Flex fan or fan clutch??? Which to use?????? [Re: gamagoat6x6] #103294 08/11/08 06:54 PM 08/11/08 06:54 PM
Joined: Dec 2007 Posts: 18,160 Mass DAYCLONA I Live Here
DAYCLONA I Live Here Joined: Dec 2007 Posts: 18,160 Mass	Why didn`t everything get `em from the factory? because they`re expensive to produce so they were reserved for things that really needed good cooling like top of the line heavily optioned cars and HD trucks. In 69 the Daytonas were equipped with fixed HD 5 blade fans.......the following year the Superbirds were equipped with thermal 5 blade clutch fans.........led to a TSB, to recall/ replace the clutch fans with a fixed fan due to overheating problems amonst Bird owners.......the "open", grille frontal area for cooling of a Tona' vs Bird, is the same, both cars are equipped identically, so engine/ options don't come into play?......so that leaves the fan as the problem 4612470-0000a.jpg (91 downloads)

Re: Flex fan or fan clutch??? Which to use?????? [Re: DAYCLONA] #103295 08/11/08 07:00 PM 08/11/08 07:00 PM
Joined: Apr 2004 Posts: 1,396 Mass dgc333 pro stock
dgc333 pro stock Joined: Apr 2004 Posts: 1,396 Mass	Quote: Quote: What are the ups and downs to both? Which work better? Thanks!! Neither,,,,,,use a fixed 5 or 7 blade factory fan,....it's not like that 5 HP loss is gonna be noticed........but 200+ degrees F....will And be sure to use a full shroud...... I have read that you can save up to 20HP with a clutch fan over a fixed blade fan. Dave Clement Pembroke, MA 03 PT Cruiser GT Turbo 99 Dakota SLT+ CC 4x4 68 Barracuda sport coupe http://home.comcast.net/~dgc333/

Re: Flex fan or fan clutch??? Which to use?????? [Re: dgc333] #103296 08/11/08 07:07 PM 08/11/08 07:07 PM
Joined: Dec 2007 Posts: 18,160 Mass DAYCLONA I Live Here
DAYCLONA I Live Here Joined: Dec 2007 Posts: 18,160 Mass	I have read that you can save up to 20HP with a clutch fan over a fixed blade fan. The key word being "up to"............kinda like the lottery......"you could be a winner"...... 4612496-0000a.jpg (41 downloads)

Re: Flex fan or fan clutch??? Which to use?????? [Re: dgc333] #103297 08/11/08 07:09 PM 08/11/08 07:09 PM
Joined: Jan 2003 Posts: 1,482 Lake Orion, MI goldduster318 pro stock
goldduster318 pro stock Joined: Jan 2003 Posts: 1,482 Lake Orion, MI	my car has a 5-blade clutch fan...actually out of an early 80's D150 pickup. you just have to measure to make sure the diameter is right for the fan. Works wonderfully and I could definitely tell the difference between it and the 9 blade fixed fan it replaced. '70 Duster 470hp 340/T56 Magnum/8 3/4 3.23 Sure-Grip

Re: Flex fan or fan clutch??? Which to use?????? [Re: goldduster318] #103298 08/11/08 07:18 PM 08/11/08 07:18 PM
Joined: Jan 2003 Posts: 27,421 Balt. Md 3 383man Too Many Posts
383man Too Many Posts 3 Joined: Jan 2003 Posts: 27,421 Balt. Md	Guess I have been lucky as I have the stock 318 flex fan on my boys Dart and I check it every year. It has been fine and on the car since 1997. I also have a flex fan on my 63 that works good and the blades look fine whenever I check them so far. Ron

Re: Flex fan or fan clutch??? Which to use?????? [Re: GoManGo70Bee] #103299 08/11/08 09:16 PM 08/11/08 09:16 PM
Joined: Jan 2003 Posts: 4,574 Upper Midwest Black_Sheep master
Black_Sheep master Joined: Jan 2003 Posts: 4,574 Upper Midwest	Quote: Do you know the diameter of the MP fan? IIRC it's 15" or 15.5" so the fan to shroud gap is a bit on the large side... '69 Plymouth GTX See you on the street...

Re: Flex fan or fan clutch??? Which to use?????? [Re: Black_Sheep] #103300 08/12/08 06:46 AM 08/12/08 06:46 AM
Joined: Jan 2003 Posts: 21,088 Niles , Ohio T therocks oh wait.but hey.lets see.oh yeah.
therocks oh wait.but hey.lets see.oh yeah. T Joined: Jan 2003 Posts: 21,088 Niles , Ohio	I agree with 383 man.ve had the same stainless flex on my 12.5 built 440 for at least 15 years.No problems and it runs under 190 all day.Ive run them since the 70s when I plowed snow.I run only stainless.Only had one fan come apart and it was a factory one.My rad in the 65 is stone stock never been touched and still cools great.We also run them on my kids built 360 and the 413.Rocky Chrysler Firepower

Re: Flex fan or fan clutch??? Which to use?????? [Re: GoManGo70Bee] #103301 08/12/08 07:14 AM 08/12/08 07:14 AM
Joined: Jul 2005 Posts: 327 pittsburgh,Pa. M mikepar enthusiast
mikepar enthusiast M Joined: Jul 2005 Posts: 327 pittsburgh,Pa.	Electric fan

Re: Flex fan or fan clutch??? Which to use?????? [Re: therocks] #103302 08/12/08 07:16 AM 08/12/08 07:16 AM
Joined: Jul 2008 Posts: 30,537 Florida STAYcation dOc ! The village idiot's idiot
dOc ! The village idiot's idiot Joined: Jul 2008 Posts: 30,537 Florida STAYcation	NONE of the above !! Get an electric puller ...works ONLY when necessary. Both the flex and clutch fans "work" alot of the times ...when their assist is not needed !!

Re: Flex fan or fan clutch??? Which to use?????? [Re: DAYCLONA] #103303 08/12/08 07:19 AM 08/12/08 07:19 AM
Joined: Apr 2004 Posts: 1,396 Mass dgc333 pro stock
dgc333 pro stock Joined: Apr 2004 Posts: 1,396 Mass	Quote: Quote: I have read that you can save up to 20HP with a clutch fan over a fixed blade fan. The key word being "up to"............kinda like the lottery......"you could be a winner"...... Yea but it will always free up more power over a fixed blade fan and with the exception of the one case you sited it has no down side. Most all heavy duty and ac cooling systems came from the factory with a clutch fan (with the exception of your example). The advantage is they have a more agressive blade design that will move more air at idle where the fan is needed and rob less HP at speed when its not needed. Dave Clement Pembroke, MA 03 PT Cruiser GT Turbo 99 Dakota SLT+ CC 4x4 68 Barracuda sport coupe http://home.comcast.net/~dgc333/

Re: Flex fan or fan clutch??? Which to use?????? [Re: dgc333] #103304 08/12/08 11:11 AM 08/12/08 11:11 AM
A Anonymous Unregistered
Anonymous Unregistered A	7 blade clutch for me. always works (until they wear out) but they work well for me

Re: Flex fan or fan clutch??? Which to use?????? #103305 08/12/08 05:27 PM 08/12/08 05:27 PM
Joined: Jan 2003 Posts: 21,088 Niles , Ohio T therocks oh wait.but hey.lets see.oh yeah.
therocks oh wait.but hey.lets see.oh yeah. T Joined: Jan 2003 Posts: 21,088 Niles , Ohio	If you have to worry about maybe 5 HP you need to build a better motor period.Ive seen too many hi buck elec and clutch fan setups with big expensive radiators that overheat.My 25 buck stainless fan has been doing the job with an almost 50 year old rad for years.Ill stick with it and keep upwards of between 200 and a thousand or more dollars in my pocket.Rocky Last edited by therocks; 08/12/08 05:27 PM. Chrysler Firepower

Re: Flex fan or fan clutch??? Which to use?????? [Re: therocks] #103306 08/12/08 06:10 PM 08/12/08 06:10 PM
Joined: Apr 2004 Posts: 1,396 Mass dgc333 pro stock
dgc333 pro stock Joined: Apr 2004 Posts: 1,396 Mass	A clutch fan is certainly not a big buck item and the free up a lot more than 5 HP. It was stock on most cars with heavy duty cooling or AC. Even if you don't have one a brand new thermostatic clutch is less than $40 at the corner parts store. Since so many cars came with them the actual fan is available at any junk yard for a couple of bucks. The hub and bolt circle of the fan is common between Mopar, GM and Ford so just pick one the diameter you need (just make sure its not a reverse rotation fan). I have one from a mid 80's Monte Carlo in my 68 Barracuda with a stock 72 vintage heavy duty radiator, it will idle all day in mid 90's summer traffic without the gauge climbing. Dave Clement Pembroke, MA 03 PT Cruiser GT Turbo 99 Dakota SLT+ CC 4x4 68 Barracuda sport coupe http://home.comcast.net/~dgc333/

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