Flex fan vs clutch fan dyno

Apr 06, 2020 · These tests established that a bottom-feeder stock, no-clutch, mechanical fan robs about as much as 50 hp on the top-end (no bull). Even the best steel-bladed flex-fan still costs upwards of 20 hp. May 07, 2004 · 46. 48. Covington. 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. Jul 02, 2022 · Clutch fans are more durable and can handle more heat than flex fans, making them a better option for vehicles that frequently tow or carry heavy loads. Flex fans, on the other hand, are more affordable and easier to install than clutch fans. Ultimately, the best fan for your vehicle depends on your specific needs and driving habits. If the electric fan debate comes back to a pure power issue I would call it near to a wash with a high quality fan and no alternator vs. an electric fan with an alternator. If it comes back to reliability and repeatability then the extra insurance an alternator gives plus the ability to keep your motor cool during cautions and red flags sounds ...Jul 31, 2003 · 227 Posts. #3 · Jul 31, 2003. Over on an A/C board, they seem to recoment staying away from the flex fan and sticking with the stock unit, or even upgrade to a newer stock unit with more blades (I think 96+ has a better electric fan on the XJs with a bunch more blades than the standard 5 (?) blade electric (was that Kingsize that pointed this out? Apr 06, 2020 · These tests established that a bottom-feeder stock, no-clutch, mechanical fan robs about as much as 50 hp on the top-end (no bull). Even the best steel-bladed flex-fan still costs upwards of 20 hp. Electric radiator fan conversion kits Jun 10, 2018 · A flex fan and a clutch fan operate in the same basic manner. The blades of the flex fan flatten out for less pitch to reduce the amount of air it moves and to lower drag on the engine. The clutch on the clutch fan slips for the same reason. The primary advantage to a flex fan is that the assembly can be shorter for use in cramped engine bays In this video, I finally put the myth to rest as to whether a clutch style/mechanical radiator fan sucks power from your engine! Enjoy!Injection Connection, ...Flex fans work like clutches the fan blades will actual straighten out at speed, so there is still loss but not the 20 to 40 hp. Electric is the way to go for cool HP. i would recommend a switch so on a cruise you can turn it off because it is not doing anything at speed. Good luck and cool runnings.... 66coupe289 Registered Joined Sep 14, 2001Changed the fan to a stock clutch fan-no more problems. Flex fans are junk. Keep the stock clutch fan or install electric fans. The electric fans don't draw enough power to hurt your HP. lsejlowe Premium Member Joined Jan 1, 2004 10,261 Posts #3 · Apr 29, 2009A Flex-Fan w/Billet Aluminum Spacer or a Black Magic Electric Fan: The Flex-Fan has fan blades that flatten out at higher RPM to reduce fan drag. At lower RPM, the blades return to their original shape to pull the maximum amount of air through the radiator and fan shroud. It is important to understand that a Flex-Fan is most efficient when it ...Apr 27, 2018 · This dual electric fan kit fits 2003-2009 Dodge Ram trucks equipped with the 5.9-liter or the 6.7-liter Cummins. With this, users can recover up to 27 horsepower and boost fuel economy by up to 6 percent by replacing the stock clutch fan assembly with this dual electric fan system. It features two 15-inch S-Blade electric fans and a Flex-A-Lite ... It rarely fails, although it can age and the clutch may not work as well after 8-10 years. Until then, the clutch keeps the fan from over spinning based on temperature it reads. The primary benefit of an electric fan is that it theoretically removes the load from the engine, especially because it can be configured to only come on when needed.Dec 26, 2019 · I dyno'd my Sammy at 57hp* of a rated 64 (EFI model) with factory old clutch fan. Which between drivetrain loss and parasitics losses seems pretty good. So I'd either leave it stock or go e-fan personally. Like AxlesUp said, the fan often isn't needed a lot of the time. Jun 27, 2007 · I'd say clutch fan would be my last choice, unless you have heating problems. Flex fan is the easiest/cheapest/most reliable. If that doesn't get the job done, or if you're concerned with that last 2hp, then skip past the clutch fan and just get a good electric fan setup. 1 - Max cooling - large aftermarket fixed fan with a good full shroud and a big multi-core radiator. 2 - Very good cooling - large HD clutch fan, with a good full shroud and big radiator. 3 - Electric high capacity - Very large dual electric fan and buy radiator to fit fan, adapt to truck to include relayed power.The vast majority of the vehicles being manufactured today use some type of electric radiator fan and it's extremely rare to hear anyone complain of overheated engines. Many off-road racing trucks also use electric radiator fans without any problem, so it would seem nonsensical to be fearful that an e-fan on a Ranger won't keep it's engine cool.The vast majority of the vehicles being manufactured today use some type of electric radiator fan and it's extremely rare to hear anyone complain of overheated engines. Many off-road racing trucks also use electric radiator fans without any problem, so it would seem nonsensical to be fearful that an e-fan on a Ranger won't keep it's engine cool.These tests established that a bottom-feeder stock, no-clutch, mechanical fan robs about as much as 50 hp on the top-end (no bull). Even the best steel-bladed flex-fan still costs upwards of 20 hp.Jan 09, 2012 · I'm not talking about a electric fan the flex fan bolts directly to the front of the engine and spins all the time. The fan on a fan clutch spins all the time too, just at more/less of a percentage when hot/cold. It doesn't STOP, it just spins slower/faster depending on NEED. Like a communist government. No fan = 496hp Electric = 494hp Thermal clutch = 487hp Nonthermal clutch = 485hp HD thermal = 476hp HP flex fan = 476hp Stock 4 blade = 473hp Low-profile flex = 466hp One piece plastic flex = 460hp OE replacement 6 blade = 449hpSee full list on carsupercare.com 1 - Max cooling - large aftermarket fixed fan with a good full shroud and a big multi-core radiator. 2 - Very good cooling - large HD clutch fan, with a good full shroud and big radiator. 3 - Electric high capacity - Very large dual electric fan and buy radiator to fit fan, adapt to truck to include relayed power.In every dyno test I've seen over the years, the flex fan has about the same HP loss as a thermostatic clutch fan does at high RPM. They use a heat gun to heat-up the clutch fan so it will disengage on the dyno. The clutch fan moves more air at lower RPM while the clutch is engaged though. If you have a drag car, an electric is the way to go.In every dyno test I've seen over the years, the flex fan has about the same HP loss as a thermostatic clutch fan does at high RPM. They use a heat gun to heat-up the clutch fan so it will disengage on the dyno. The clutch fan moves more air at lower RPM while the clutch is engaged though. If you have a drag car, an electric is the way to go.Jun 01, 2005 · The fan and shroud are about $50 together at the dealer, and the fan clutch is available at any parts outlet for not much more than that. No worries about broken blades with the metal fan, no electrical gremlins to deal with on the trail, just a fan that works well all the time. The V2 with Fan kit is $1240. The CAI kit is $65. We highly recommend the V2 with Fan kit if you are serious about thoroughly squashing overheating and that irritating engine fan. This kit is THE CURE for those ills and is well worth it once you see all the benefits that come about after it is installed.FS SoCal Stock 2015 Fiesta ST - 44 ECU Tuning However, coming from being street tuners ourselves, we 2 full bolt ons + tune focus st'S getting dyno 'D!! ??? Focus ST COBB Front Mount Intercooler Kit 2013-2016 Installation Tuned 300Hp/455Nm tested by us on the Dyno ! well my roommate has a 240sx and is claiming 40 hp gain from a hot air intake and a eclectic fans. i have my doubts if he is gaining anything before i go out and buy a electric fan and hot air intake please help me with a goo:waytogo:d decisionsJul 24, 2012 · The clutch also limits how fast the fan can spin and only turns the fan at a fraction of the water pump speed, depending on engine speed and temperature. Select a Clutch Fan for: Stock or mildly modified engines; Best overall cooling ability; Applications up to 6,000 rpm; Flex fans don’t use a clutch and therefore operate at 100 percent of ... In addition I have seen multiple dyno tests where a significant amount of power was freed up at the wheels. There have been many rag tests over then years that have shown that the most efficient (parasitic losses) engine driven fans are of the viscous clutch type. I have seen 20 to 40 fwhp HP from worst to best.Jun 15, 2022 · Clutch Fan or Flex. I have an 80, with a 350 crate motor, 20,000 miles on it. It was originally a Florida car, Long Island now, and has electric fans which constantly stay on. It also has a clutch fan. The engine is stock except for an edelbrock performer manifold, carb, and it has headers. The problem is when I run the AC the temp will rise up ... Jul 05, 2014 · Flex fans will cost you in efficiency. The fan is typically not even needed when going down the road so the clutch uncouples it saving you hp wasted to spin the fan. Guy on one of the Corvette forums tried six hubs and eight fans over 200 dyno runs with his engine. Clutch fan when uncoupled cost 2hp compared to no fan at all. Jun 13, 2013 · 1 - Solid fan 2 - Clutch fan w/ solid blades 3 - Flex fan Electric fans can be anywhere but generally poor unless you have a very capable fan and a radiator / engine compartment big enough to fit them. Unfortunately, that list also shows which eats the most power. Made the throttle response so much better. "16. It takes between 10 and 70 hp to drive the cooling fan, so cooling system maintenance can have a significant effect on fuel economy. Replacing the stock clutch fan with a Flex-a-lite twin electric fan setup is said to recover 27 hp and increase fuel mileage by 6%."In addition, the clutch is never completely disengaged, so the fan is always turning at about 30 percent of the water-pump speed. Flex fans spin at a 1:1 ratio of the water pump, but that’s still too limiting. Thus, both clutch-driven and mechanical fans are suited for mildly modified engines and should not be used for extreme performance builds. When coupled with the themo-clutch it gives up some CFMs depending on temperature etal, but doesn't eat up hp on the other end as if fixed. Notice the torque percentage difference with the clutch attached. This is due to the work it takes to get the mass of the thermo-clutch up to speed.Flex fan is good to move air at slow engine speeds and flattens out when the engine is going so that it doesnt use HP..... 2. Steel fan is great at all rpm ranges...but is large and heavy and used HP to use... is a flex fan or steel fan better..I don't have cfm numbers, but from much experience the 17" thermal clutch fan will pull the most air and eat the least amount of power for a mechanical fan. Clutch fan pulls well at idle, then clutches and floats/freewheels when road speed is high enough to provide the needed air flow or engine rpm goes higher than the fan's peak efficiency rpm.Jun 29, 2011 · With the E-fans, it blows ice cold all the time no matter whether I am doing 60mph, or driving 5mph thru a parking lot. To be honest, I probably could have achieved the same end results by leaving the clutch fan on and just adding a thin pusher fan like a flex a lite or something between the condensor and the front grill. FS SoCal Stock 2015 Fiesta ST - 44 ECU Tuning However, coming from being street tuners ourselves, we 2 full bolt ons + tune focus st'S getting dyno 'D!! ??? Focus ST COBB Front Mount Intercooler Kit 2013-2016 Installation Tuned 300Hp/455Nm tested by us on the Dyno ! Basically, how it works is that when the engine is cold, the fan turns MUCH slower than the water pump. As the engine heats up, the warmer air flowing through the radiator heats up a small bi-metal thermostatic element on the front of the fan clutch, which engages the clutch to make the fan turn faster.Changed the fan to a stock clutch fan-no more problems. Flex fans are junk. Keep the stock clutch fan or install electric fans. The electric fans don't draw enough power to hurt your HP. lsejlowe Premium Member Joined Jan 1, 2004 10,261 Posts #3 · Apr 29, 2009Jun 18, 2009 · The Volvo mechanical fan has a slip clutch so it reduces parasitic loss. The flex fans go flat as they are revved up for less hp loss. They are also much lighter than the clutch type mechanical fans so they are less load on the engine. Use what you want. It's easy to chose either way and they both work. Fixed Turbocharger Comp Outlet Temp Select Your Drive 6- blade airfoil design cast aluminum propeller provides taperlock 12246 Horton New Spacer Assy Matched Set Fan Clutch Hub Drive (51 The engine will be dyno tested checking horsepower, RPM and oil pressure The engine will be dyno tested checking horsepower, RPM and oil pressure.. Flex fans work like clutches the fan blades will actual straighten out at speed, so there is still loss but not the 20 to 40 hp. Electric is the way to go for cool HP. i would recommend a switch so on a cruise you can turn it off because it is not doing anything at speed. Good luck and cool runnings.... 66coupe289 Registered Joined Sep 14, 2001Jun 13, 2011 · Low-profile flex = 466hp One piece plastic flex = 460hp OE replacement 6 blade = 449hp If I remember correctly this was an engine dyno not a chassis dyno with a cooling tower so the clutch fans may not be locking up as much since there wasn't a radiator in front of them to add heat to induce lock up. The V2 with Fan kit is $1240. The CAI kit is $65. We highly recommend the V2 with Fan kit if you are serious about thoroughly squashing overheating and that irritating engine fan. This kit is THE CURE for those ills and is well worth it once you see all the benefits that come about after it is installed.Jun 27, 2007 · I'd say clutch fan would be my last choice, unless you have heating problems. Flex fan is the easiest/cheapest/most reliable. If that doesn't get the job done, or if you're concerned with that last 2hp, then skip past the clutch fan and just get a good electric fan setup. The fan clutch uses a viscous fl uid for cooling fan engagement, while a thermal spring operates valving controlling fl uid fl ow and fan engagement. As engine heat drops, so does the fan’s engagement to lower parasitic drag. As good as this fan clutch worked for the era, the fan only activated as fast as the engine RPM allowed. Mar 18, 2010 · mopar performance tested all available V8 fans and the viscous drive asymmetric 5 blade MP unit won. 16 hp gain over no clutch standard and flex fans. flex fans might cut wind resistance but not rotating mass which eats power. the 5 blade mp fan fits all stock big block (and probably most 57-61 V8s) 60/61 mopars and cools very well. Transmission Cooler Mounting Bracket Kit For 2003-2009 Dodge Ram 2500-3500 (Includes Cooler) Flex-A-Lite® has taken the guesswork out of selecting and mounting Learn More. Find an Online Retailer. Flex-A-Lite Extruded Core Radiator for 1967-1979 Ford Trucks. Direct-fit Flex-A-Lite® Extruded Core performance aluminum radiator for 1967-1979 ... Jul 31, 2003 · 227 Posts. #3 · Jul 31, 2003. Over on an A/C board, they seem to recoment staying away from the flex fan and sticking with the stock unit, or even upgrade to a newer stock unit with more blades (I think 96+ has a better electric fan on the XJs with a bunch more blades than the standard 5 (?) blade electric (was that Kingsize that pointed this out? So why does everyone that goes to the E-Fan talk about how great it is compared to the stock clutch fan? 1998 ZJ Laredo(Gonzo) - Built Not Bought - 3.5" lift with IRO Long Arms, Cherry Bomb Exhaust, 31x10.50R15, CAI, Custom Front Recovery System & YJ Tube BumperHigh Performance Flex Fans. Standard Rotation Stainless Steel. Standard Rotation Aluminum. Reverse Rotation Stainless Steel. Rigid Race Fans. Standard Rotation Aluminum Blade. Standard Rotation Steel Blade. Reverse Rotation Steel Blade. Fan Clutch Fans.Jun 15, 2022 · Clutch Fan or Flex. I have an 80, with a 350 crate motor, 20,000 miles on it. It was originally a Florida car, Long Island now, and has electric fans which constantly stay on. It also has a clutch fan. The engine is stock except for an edelbrock performer manifold, carb, and it has headers. The problem is when I run the AC the temp will rise up ... High Performance Flex Fans. Standard Rotation Stainless Steel. Standard Rotation Aluminum. Reverse Rotation Stainless Steel. Rigid Race Fans. Standard Rotation Aluminum Blade. Standard Rotation Steel Blade. Reverse Rotation Steel Blade. Fan Clutch Fans.Nov 2, 2017. #3. No clutch fans were ever used on a stock on a 240, that I know of. In a straight comparison of a standard fixed fan versus a clutch fan yes it dose matter. A clutch fan uses less power to turn it and getting one off a later model 300 or some other Ford engine (pre surpenetine belt drive) can be a bolt on. Good luck.Jun 15, 2022 · Clutch Fan or Flex. I have an 80, with a 350 crate motor, 20,000 miles on it. It was originally a Florida car, Long Island now, and has electric fans which constantly stay on. It also has a clutch fan. The engine is stock except for an edelbrock performer manifold, carb, and it has headers. The problem is when I run the AC the temp will rise up ... The plastic flex fan (so no clutch) dropped 23 hp. Ours is probably worse than that engaged because it's not a flex fan. ... IIRC from the wit's end turbo thread dyno results, stock only gets 130-140hp at the wheels, so that 5hp at 3500rpm to 9hp at 4500rpm is definitely enough to be felt (about 3-7%). But you'd probably get just as much gain ...May 30, 2019 · I kinda cringe everytime I see a mustang or another vehicle with an engine driven fan and no shroud. The shroud is there to direct the air through the radiator. My 96' jeep 4.0 had the top section of the fan shroud missing above the clutch fan. When I re-attached the top section, I actually noticed an improvement in my coolant temperature. switching from a direct drive fan to a clutch actuated radiator fanFew things beat an electric fan for operational quiet and efficient function. This is the Flex-a-Lite 15-inch 3,000cfm electric fan for a wide variety of radiators in the 20-inch range. Electric cooling fans should get switched power with ignition on only. Always use a fan relay kit in the interest of safety. These fans pull a lot of amps.Jun 18, 2009 · The Volvo mechanical fan has a slip clutch so it reduces parasitic loss. The flex fans go flat as they are revved up for less hp loss. They are also much lighter than the clutch type mechanical fans so they are less load on the engine. Use what you want. It's easy to chose either way and they both work. 5.5 squared is 30.25 times 3.1417 = 95.03 inches of fan area x 2 = 190 inches. 18" fan divided by 2 = 9". 9 squared is 81 times 3.1417 = 254.47 inches of fan area. Now, in comparison to the clutch and fixed blade fans, there is no real empirical data for comparison. But it's overall approach is proven.A standard clutch runs at around 60%-70% of engine speed so that's around 5700-6700 engine RPM that the fan is safe for. What aggravates me is that Summit carries several heavy duty clutches (which run at 80%-90% of engine speed) but only standard duty fans. I guess those clutches have to be used with a factory fan from an RV or HD truck. RSigh, this topic again. Electric fans FTW. Engine driven fans suck. But go ahead and install that flex fan and see for yourself how much they suck. Flex fans rob HP 100% of the time. Clutch fans rob HP 100% of the time too. Only clutch fans use less HP when idling but they still spin the fan 100% of the time even when not needed.Apr 06, 2020 · These tests established that a bottom-feeder stock, no-clutch, mechanical fan robs about as much as 50 hp on the top-end (no bull). Even the best steel-bladed flex-fan still costs upwards of 20 hp. May 26, 2014 · The Corvette has a three quarter inch diameter shaft to support high RPM operation, all other water pumps use a five eighths inch diameter shaft. Additionally all Corvettes have a thermal fan clutch. In addition to reducing the fans RPM except when the radiator is very hot, it also limits the RPM of the fan is 4,500 RPM. Dec 18, 2014 · Opinion: 1. Flex fan is dangerous. 2. Electric fan is inefficient: Belt drive a generator to charge a battery and/or provide current to run an electric motor to turn a fan. 3. Belt drive a fan. #3 is the way to go unless belt drive of the fan is impractical as--for example--is the case on transverse-mounted engines. Opinion: 1. Flex fan is dangerous. 2. Electric fan is inefficient: Belt drive a generator to charge a battery and/or provide current to run an electric motor to turn a fan. 3. Belt drive a fan. #3 is the way to go unless belt drive of the fan is impractical as--for example--is the case on transverse-mounted engines.Sep 01, 2003 · That's why the fan clutch improves fuel mileage, it reduces drag on the engine when it's free wheeling at travel speeds. The switch from a 3 bladed fan to 6 or the flex fan shouldn't have made any difference at highway speeds, there's supposed to be enough air flow to handle the cooling. Black Magic electric fan: 494 hp Thermal clutch fan: 487 hp Nonthermal clutch fan: 485 hp Heavy duty thermal clutch fan: 476 hp High performance flex fan: 476 hp Stock four blade fan: 473 hp Low profile flex fan: 466 hp One piece plastic flex fan: 460 hp OE replacement six blade rigid fan: 449 hpOpinion: 1. Flex fan is dangerous. 2. Electric fan is inefficient: Belt drive a generator to charge a battery and/or provide current to run an electric motor to turn a fan. 3. Belt drive a fan. #3 is the way to go unless belt drive of the fan is impractical as--for example--is the case on transverse-mounted engines.FS SoCal Stock 2015 Fiesta ST - 44 ECU Tuning However, coming from being street tuners ourselves, we 2 full bolt ons + tune focus st'S getting dyno 'D!! ??? Focus ST COBB Front Mount Intercooler Kit 2013-2016 Installation Tuned 300Hp/455Nm tested by us on the Dyno ! [email protected] Pro - loud scream of stock fan is gone along with no more drag on the motor Pro - A/C does seem cooler Pro - temps stay around 192 consistently and a little higher with A/C and at higher rpm Pro - fairly easy install if you have some mechanical experience and some wiring experience. Con - Fan clutch bolt was an #$%^&# to get offAs engine coolant temperature rises within the radiator, the air passing through the radiator heats the spring coil on the fan clutch Since the electric fan only runs when needed, less noise is made i want it to run when it needs to not contantly running nor do i want a switch This is the new harness that many customers have been asking about ... Jul 02, 2022 · Clutch fans are more durable and can handle more heat than flex fans, making them a better option for vehicles that frequently tow or carry heavy loads. Flex fans, on the other hand, are more affordable and easier to install than clutch fans. Ultimately, the best fan for your vehicle depends on your specific needs and driving habits. May 07, 2004 · 46. 48. Covington. 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. I tried running flex fans on a couple of my pontiacs and hated them, never cooled worth crap. Went to a factory fan clutch and factory a/c fans ( a/c fans are bigger than non a/c ) and never had another problem. Every motor I've built from the early 90`s on have had factory fans.Jun 11, 2006 · Clutch fans have a similar limitation, that is whey flex fans with bimetallic thermostats were developed. Ultimately, electric fans are the best solution as turning on the fan when necessary. There are a lot of variables for airflow with fans. In general more blades are better. The amount of airflow also depends on how close the fan is to the ... Jun 18, 2009 · The Volvo mechanical fan has a slip clutch so it reduces parasitic loss. The flex fans go flat as they are revved up for less hp loss. They are also much lighter than the clutch type mechanical fans so they are less load on the engine. Use what you want. It's easy to chose either way and they both work. FS SoCal Stock 2015 Fiesta ST - 44 ECU Tuning However, coming from being street tuners ourselves, we 2 full bolt ons + tune focus st'S getting dyno 'D!! ??? Focus ST COBB Front Mount Intercooler Kit 2013-2016 Installation Tuned 300Hp/455Nm tested by us on the Dyno ! Dec 26, 2019 · I dyno'd my Sammy at 57hp* of a rated 64 (EFI model) with factory old clutch fan. Which between drivetrain loss and parasitics losses seems pretty good. So I'd either leave it stock or go e-fan personally. Like AxlesUp said, the fan often isn't needed a lot of the time. Mar 18, 2010 · mopar performance tested all available V8 fans and the viscous drive asymmetric 5 blade MP unit won. 16 hp gain over no clutch standard and flex fans. flex fans might cut wind resistance but not rotating mass which eats power. the 5 blade mp fan fits all stock big block (and probably most 57-61 V8s) 60/61 mopars and cools very well. No fan = 496hp Electric = 494hp Thermal clutch = 487hp Nonthermal clutch = 485hp HD thermal = 476hp HP flex fan = 476hp Stock 4 blade = 473hp Low-profile flex = 466hp One piece plastic flex = 460hp OE replacement 6 blade = 449hpWith the E-fans, it blows ice cold all the time no matter whether I am doing 60mph, or driving 5mph thru a parking lot. To be honest, I probably could have achieved the same end results by leaving the clutch fan on and just adding a thin pusher fan like a flex a lite or something between the condensor and the front grill.Jun 13, 2011 · Low-profile flex = 466hp One piece plastic flex = 460hp OE replacement 6 blade = 449hp If I remember correctly this was an engine dyno not a chassis dyno with a cooling tower so the clutch fans may not be locking up as much since there wasn't a radiator in front of them to add heat to induce lock up. Electric radiator fan conversion kits Jul 02, 2022 · Clutch fans are more durable and can handle more heat than flex fans, making them a better option for vehicles that frequently tow or carry heavy loads. Flex fans, on the other hand, are more affordable and easier to install than clutch fans. Ultimately, the best fan for your vehicle depends on your specific needs and driving habits. Clutch Fans have fixed blades. They require a coupler to engage and disengage the fan. This coupler is called the Fan Clutch. Flex Fans do not need a clutch. At high rpm, the blades "flatten out." This achieves the same function as disengaging the fan. However, flex fans require a Fan Spacer.Jul 31, 2003 · 227 Posts. #3 · Jul 31, 2003. Over on an A/C board, they seem to recoment staying away from the flex fan and sticking with the stock unit, or even upgrade to a newer stock unit with more blades (I think 96+ has a better electric fan on the XJs with a bunch more blades than the standard 5 (?) blade electric (was that Kingsize that pointed this out? May 30, 2019 · I kinda cringe everytime I see a mustang or another vehicle with an engine driven fan and no shroud. The shroud is there to direct the air through the radiator. My 96' jeep 4.0 had the top section of the fan shroud missing above the clutch fan. When I re-attached the top section, I actually noticed an improvement in my coolant temperature. If the electric fan debate comes back to a pure power issue I would call it near to a wash with a high quality fan and no alternator vs. an electric fan with an alternator. If it comes back to reliability and repeatability then the extra insurance an alternator gives plus the ability to keep your motor cool during cautions and red flags sounds ...Apr 02, 2018 · Shroud is needed. If no clutch fan (best), use a regular hd fan. Do not use a flex fan. Flex fans are crap. As they flex towards flatness, that also = a flat spinning disc, = no air flow through rad. So why does everyone that goes to the E-Fan talk about how great it is compared to the stock clutch fan? 1998 ZJ Laredo(Gonzo) - Built Not Bought - 3.5" lift with IRO Long Arms, Cherry Bomb Exhaust, 31x10.50R15, CAI, Custom Front Recovery System & YJ Tube BumperUnity Motorsports Garage tests one of the age old questions... How much power do you lose running a Flex Fan on your Hotrod? We took Casper My F100 and foun... Dec 16, 2014 · The fixed fans and flex fans were inferior to the clutch fan. Electric fans have the advantage of being able to cool the engine after it is shut down, but aren't likely to cool as well as a properly set up clutch fan. Remember that the electric fans are designed for today's small aluminum engines, not for the old large cast iron engines. Transmission Cooler Mounting Bracket Kit For 2003-2009 Dodge Ram 2500-3500 (Includes Cooler) Flex-A-Lite® has taken the guesswork out of selecting and mounting Learn More. Find an Online Retailer. Flex-A-Lite Extruded Core Radiator for 1967-1979 Ford Trucks. Direct-fit Flex-A-Lite® Extruded Core performance aluminum radiator for 1967-1979 ... A Flex-Fan w/Billet Aluminum Spacer or a Black Magic Electric Fan: The Flex-Fan has fan blades that flatten out at higher RPM to reduce fan drag. At lower RPM, the blades return to their original shape to pull the maximum amount of air through the radiator and fan shroud. It is important to understand that a Flex-Fan is most efficient when it ...switching from a direct drive fan to a clutch actuated radiator fanThe plastic flex fan (so no clutch) dropped 23 hp. Ours is probably worse than that engaged because it's not a flex fan. ... IIRC from the wit's end turbo thread dyno results, stock only gets 130-140hp at the wheels, so that 5hp at 3500rpm to 9hp at 4500rpm is definitely enough to be felt (about 3-7%). But you'd probably get just as much gain ...Jun 27, 2007 · I'd say clutch fan would be my last choice, unless you have heating problems. Flex fan is the easiest/cheapest/most reliable. If that doesn't get the job done, or if you're concerned with that last 2hp, then skip past the clutch fan and just get a good electric fan setup. Apr 15, 2020 · On the Dyno. We strapped our 2019 Honda Civic Si to the dyno to get a baseline. On our Dynojet, the Si put down 189.81 peak whp and 190.58 lb-ft of torque. This was accomplished when running on the factory 18.87 psi of boost. Torque peaks early on from 3,000 RPM to 3,700 RPM before slowly dropping. Sigh, this topic again. Electric fans FTW. Engine driven fans suck. But go ahead and install that flex fan and see for yourself how much they suck. Flex fans rob HP 100% of the time. Clutch fans rob HP 100% of the time too. Only clutch fans use less HP when idling but they still spin the fan 100% of the time even when not needed.In addition, the clutch is never completely disengaged, so the fan is always turning at about 30 percent of the water-pump speed. Flex fans spin at a 1:1 ratio of the water pump, but that's still too limiting. Thus, both clutch-driven and mechanical fans are suited for mildly modified engines and should not be used for extreme performance builds.This dual electric fan kit fits 2003-2009 Dodge Ram trucks equipped with the 5.9-liter or the 6.7-liter Cummins. With this, users can recover up to 27 horsepower and boost fuel economy by up to 6 percent by replacing the stock clutch fan assembly with this dual electric fan system. It features two 15-inch S-Blade electric fans and a Flex-A-Lite ...With the E-fans, it blows ice cold all the time no matter whether I am doing 60mph, or driving 5mph thru a parking lot. To be honest, I probably could have achieved the same end results by leaving the clutch fan on and just adding a thin pusher fan like a flex a lite or something between the condensor and the front grill.Transmission Cooler Mounting Bracket Kit For 2003-2009 Dodge Ram 2500-3500 (Includes Cooler) Flex-A-Lite® has taken the guesswork out of selecting and mounting Learn More. Find an Online Retailer. Flex-A-Lite Extruded Core Radiator for 1967-1979 Ford Trucks. Direct-fit Flex-A-Lite® Extruded Core performance aluminum radiator for 1967-1979 ... Which is a better conversion in both performance gain and cooling efficiency taking into consideration the stock dimensions of a '65 radiator? 1. Electric fan with custom shroud; or 2. Clutch fan with 3" shroud (fan is plastic). For those who have gone to an electric fan, is there a "one-stop"...The rpm-activated clutch fan outperformed all the flex fans tested but was inferior to the fixed-blade O.E. fan below 3,500 rpm. In conclusion, the best power can still be made with no fan at all. Short of this, a thermo-controlled clutch fan is the best choice for optimum power and cooling capacity. CHP These tests established that a bottom-feeder stock, no-clutch, mechanical fan robs about as much as 50 hp on the top-end (no bull). Even the best steel-bladed flex-fan still costs upwards of 20 hp.It rarely fails, although it can age and the clutch may not work as well after 8-10 years. Until then, the clutch keeps the fan from over spinning based on temperature it reads. The primary benefit of an electric fan is that it theoretically removes the load from the engine, especially because it can be configured to only come on when needed.Dec 18, 2014 · Opinion: 1. Flex fan is dangerous. 2. Electric fan is inefficient: Belt drive a generator to charge a battery and/or provide current to run an electric motor to turn a fan. 3. Belt drive a fan. #3 is the way to go unless belt drive of the fan is impractical as--for example--is the case on transverse-mounted engines. Few things beat an electric fan for operational quiet and efficient function. This is the Flex-a-Lite 15-inch 3,000cfm electric fan for a wide variety of radiators in the 20-inch range. Electric cooling fans should get switched power with ignition on only. Always use a fan relay kit in the interest of safety. These fans pull a lot of amps.May 07, 2004 · 46. 48. Covington. 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. Changed the fan to a stock clutch fan-no more problems. Flex fans are junk. Keep the stock clutch fan or install electric fans. The electric fans don't draw enough power to hurt your HP. lsejlowe Premium Member Joined Jan 1, 2004 10,261 Posts #3 · Apr 29, 2009On the dyno I made 1hp more than with the stock fan, but lost 3tq. Yes, a real dyno, the same dyno, and yes, it corrects for weather. At the track I saw no performance gains. None. The car does sound a lot better without the Clutch fan whirrin' under there. I got mine slightly used for $75 2 years ago and it still works flawlessly.Daves assertions are indisputable. If you compare CFM to CFM, there will not be any performance gain by using an electric fan. The only way the electric fan could be more efficient is if it were able to more accurately tune the air flow to the needs of the engine minute by minute.That would also assume that the OEM fan is substantially over cooling the engine most of the time.Basically, how it works is that when the engine is cold, the fan turns MUCH slower than the water pump. As the engine heats up, the warmer air flowing through the radiator heats up a small bi-metal thermostatic element on the front of the fan clutch, which engages the clutch to make the fan turn faster.Engine Masters did a dyno test on an OEM clutch fan vs. a flex fan, vs. a fan with no clutch. The conclusion was that the clutch fan used MUCH less hp than the flex fan or fan with no clutch. I would either run a clutch fan or electric fans. 1964 Chevy II Nova. Kuntz & Co. 383 Stroker, 4L60E, 3,000 stall, 9" with 3.50 gears. B bracketchev70Flex fans work like clutches the fan blades will actual straighten out at speed, so there is still loss but not the 20 to 40 hp. Electric is the way to go for cool HP. i would recommend a switch so on a cruise you can turn it off because it is not doing anything at speed. Good luck and cool runnings.... 66coupe289 Registered Joined Sep 14, 2001Apr 02, 2018 · Shroud is needed. If no clutch fan (best), use a regular hd fan. Do not use a flex fan. Flex fans are crap. As they flex towards flatness, that also = a flat spinning disc, = no air flow through rad. We had a 2006 TBSS on the dyno this week that we had previously tuned in the fall. It was hot as hell in the dyno room and we still picked up 21 rwhp and 29ftlbs of torque with a PWM fan and powerbond underdrive pulley ... Other than that, e-fans are not as reliable and do not cool as well as a factory engine driven clutch fan. (aftermarket ...May 07, 2004 · 46. 48. Covington. 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. Mar 18, 2010 · mopar performance tested all available V8 fans and the viscous drive asymmetric 5 blade MP unit won. 16 hp gain over no clutch standard and flex fans. flex fans might cut wind resistance but not rotating mass which eats power. the 5 blade mp fan fits all stock big block (and probably most 57-61 V8s) 60/61 mopars and cools very well. Jun 13, 2011 · Low-profile flex = 466hp One piece plastic flex = 460hp OE replacement 6 blade = 449hp If I remember correctly this was an engine dyno not a chassis dyno with a cooling tower so the clutch fans may not be locking up as much since there wasn't a radiator in front of them to add heat to induce lock up. Jun 18, 2009 · The Volvo mechanical fan has a slip clutch so it reduces parasitic loss. The flex fans go flat as they are revved up for less hp loss. They are also much lighter than the clutch type mechanical fans so they are less load on the engine. Use what you want. It's easy to chose either way and they both work. Jun 15, 2022 · Clutch Fan or Flex. I have an 80, with a 350 crate motor, 20,000 miles on it. It was originally a Florida car, Long Island now, and has electric fans which constantly stay on. It also has a clutch fan. The engine is stock except for an edelbrock performer manifold, carb, and it has headers. The problem is when I run the AC the temp will rise up ... Flex fans vs. clutch fans vs electric fans. Jump to Latest Follow 21 - 24 of 24 Posts. Prev ... Car Craft mag did a big dyno test on a 496HP SBC on a large selection of fans....the worst offender, the Flex-a-Lite replacement for the GM 6-blade rigid fan, lost a whopping 47 hp!! Archived on the Cleveland engines forum... Cleveland Photos:High Performance Flex Fans. Standard Rotation Stainless Steel. Standard Rotation Aluminum. Reverse Rotation Stainless Steel. Rigid Race Fans. Standard Rotation Aluminum Blade. Standard Rotation Steel Blade. Reverse Rotation Steel Blade. Fan Clutch Fans.Sigh, this topic again. Electric fans FTW. Engine driven fans suck. But go ahead and install that flex fan and see for yourself how much they suck. Flex fans rob HP 100% of the time. Clutch fans rob HP 100% of the time too. Only clutch fans use less HP when idling but they still spin the fan 100% of the time even when not needed.Changed the fan to a stock clutch fan-no more problems. Flex fans are junk. Keep the stock clutch fan or install electric fans. The electric fans don't draw enough power to hurt your HP. lsejlowe Premium Member Joined Jan 1, 2004 10,261 Posts #3 · Apr 29, 2009These tests established that a bottom-feeder stock, no-clutch, mechanical fan robs about as much as 50 hp on the top-end (no bull). Even the best steel-bladed flex-fan still costs upwards of 20 hp.Unity Motorsports Garage tests one of the age old questions... How much power do you lose running a Flex Fan on your Hotrod? We took Casper My F100 and foun... Actually, because of the blade pitch, the clutch fan will move MUCH more air than a flex fan at any given RPM, WHEN THE CLUTCH IS ENGAGED. When it's not engaged, it obviously moves less air and requires less power. ... does a flex fan really only take 2HP more than an electric fan setup? has anybody seen dyno sheets to prove this cuz if thats ...In this video, I finally put the myth to rest as to whether a clutch style/mechanical radiator fan sucks power from your engine! Enjoy!Injection Connection, ...Clutch Fans have fixed blades. They require a coupler to engage and disengage the fan. This coupler is called the Fan Clutch. Flex Fans do not need a clutch. At high rpm, the blades "flatten out." This achieves the same function as disengaging the fan. However, flex fans require a Fan Spacer.I don't have cfm numbers, but from much experience the 17" thermal clutch fan will pull the most air and eat the least amount of power for a mechanical fan. Clutch fan pulls well at idle, then clutches and floats/freewheels when road speed is high enough to provide the needed air flow or engine rpm goes higher than the fan's peak efficiency rpm.Apr 03, 2020 · Clutch fans are the right choice for stock or mildly modified engines. They will adequately cool the engine. Just be sure to use the fan and clutch designed for your application. Using the wrong parts could result in poor cooling, excessive noise, reduced fuel economy, and/or fan clutch failure. For high rpm use, flex fans are considered an ... Aug 09, 2012 · The clutch fan draws power from the engine due to the added load.... The electric fan saves power due to no load on the engine.... Clutch fans are better because they only apply a load at idle or low speed and don't require wiring... Electric fans save power but add weight and require a lot of wiring... Aug 8, 2012. Apr 27, 2018 · This dual electric fan kit fits 2003-2009 Dodge Ram trucks equipped with the 5.9-liter or the 6.7-liter Cummins. With this, users can recover up to 27 horsepower and boost fuel economy by up to 6 percent by replacing the stock clutch fan assembly with this dual electric fan system. It features two 15-inch S-Blade electric fans and a Flex-A-Lite ... Opinion: 1. Flex fan is dangerous. 2. Electric fan is inefficient: Belt drive a generator to charge a battery and/or provide current to run an electric motor to turn a fan. 3. Belt drive a fan. #3 is the way to go unless belt drive of the fan is impractical as--for example--is the case on transverse-mounted engines.Jul 24, 2012 · The clutch also limits how fast the fan can spin and only turns the fan at a fraction of the water pump speed, depending on engine speed and temperature. Select a Clutch Fan for: Stock or mildly modified engines; Best overall cooling ability; Applications up to 6,000 rpm; Flex fans don’t use a clutch and therefore operate at 100 percent of ... FS SoCal Stock 2015 Fiesta ST - 44 ECU Tuning However, coming from being street tuners ourselves, we 2 full bolt ons + tune focus st'S getting dyno 'D!! ??? Focus ST COBB Front Mount Intercooler Kit 2013-2016 Installation Tuned 300Hp/455Nm tested by us on the Dyno ! Engine Masters did a dyno test on an OEM clutch fan vs. a flex fan, vs. a fan with no clutch. The conclusion was that the clutch fan used MUCH less hp than the flex fan or fan with no clutch. I would either run a clutch fan or electric fans. 1964 Chevy II Nova. Kuntz & Co. 383 Stroker, 4L60E, 3,000 stall, 9" with 3.50 gears. B bracketchev70switching from a direct drive fan to a clutch actuated radiator fanI tried running flex fans on a couple of my pontiacs and hated them, never cooled worth crap. Went to a factory fan clutch and factory a/c fans ( a/c fans are bigger than non a/c ) and never had another problem. Every motor I've built from the early 90`s on have had factory fans.The standard fan runs all the time, it comes on fully not only for coolant temperature, but also for charge air temp. If you need to put on enough electric fans flow the same amount of air that the standard fan does, and you have to put on a larger alternator to make it work, then I can see no possible way that you could gain HP.Sep 27, 2004 · I ran a flex fan for years and what bugged me more than anything was the noise. I ran 3" exhaust with cherry bombs, and the fan was still louder than the exhaust. I also drag race, and have read that they have a habit of exploding at high rpm, so I finally switched to a stock type clutch fan for less drag at high speeds. The rpm-activated clutch fan outperformed all the flex fans tested but was inferior to the fixed-blade O.E. fan below 3,500 rpm. In conclusion, the best power can still be made with no fan at all. Short of this, a thermo-controlled clutch fan is the best choice for optimum power and cooling capacity. CHPI have a dual 1 1/4" tube aluminum rad & stock shroud. It had an engine driven flex fan before and seems better with the clutch fan - definitely quieter. I drove about 40 miles with the fan just free-wheeling when the clutch went bad and temperature was fine at 50 mp, but would start to get hot when slowed down and stopped at a cross roads.The V2 with Fan kit is $1240. The CAI kit is $65. We highly recommend the V2 with Fan kit if you are serious about thoroughly squashing overheating and that irritating engine fan. This kit is THE CURE for those ills and is well worth it once you see all the benefits that come about after it is installed.switching from a direct drive fan to a clutch actuated radiator fanJul 02, 2022 · Clutch fans are more durable and can handle more heat than flex fans, making them a better option for vehicles that frequently tow or carry heavy loads. Flex fans, on the other hand, are more affordable and easier to install than clutch fans. Ultimately, the best fan for your vehicle depends on your specific needs and driving habits. A standard clutch runs at around 60%-70% of engine speed so that's around 5700-6700 engine RPM that the fan is safe for. What aggravates me is that Summit carries several heavy duty clutches (which run at 80%-90% of engine speed) but only standard duty fans. I guess those clutches have to be used with a factory fan from an RV or HD truck. RThe clutch fan does not improve cooling vs. a fixed fan with the same blade count and pitch — what it does is enable using a more aggressive fan profile without costing as much HP to drive it at high speeds. So your typical clutch fan has more or bigger blades, possibly with a more aggressive pitch, than a fixed fan.19" Heavy Duty Stainless Steel Standard Rotation Flex Fan, Chrome Hub. Product details. Remote Filter Mount Accessories. Remote Filter Mounts. Cooling Pans. Cooling Pan Accessories. Fan Clutches. Performance Fuel Pumps.In addition, the clutch is never completely disengaged, so the fan is always turning at about 30 percent of the water-pump speed. Flex fans spin at a 1:1 ratio of the water pump, but that's still too limiting. Thus, both clutch-driven and mechanical fans are suited for mildly modified engines and should not be used for extreme performance builds.In this video, I finally put the myth to rest as to whether a clutch style/mechanical radiator fan sucks power from your engine! Enjoy!Injection Connection, ... Mar 18, 2010 · mopar performance tested all available V8 fans and the viscous drive asymmetric 5 blade MP unit won. 16 hp gain over no clutch standard and flex fans. flex fans might cut wind resistance but not rotating mass which eats power. the 5 blade mp fan fits all stock big block (and probably most 57-61 V8s) 60/61 mopars and cools very well. switching from a direct drive fan to a clutch actuated radiator fan No fan = 496hp Electric = 494hp Thermal clutch = 487hp Nonthermal clutch = 485hp HD thermal = 476hp HP flex fan = 476hp Stock 4 blade = 473hp Low-profile flex = 466hp One piece plastic flex = 460hp OE replacement 6 blade = 449hpI tried running flex fans on a couple of my pontiacs and hated them, never cooled worth crap. Went to a factory fan clutch and factory a/c fans ( a/c fans are bigger than non a/c ) and never had another problem. Every motor I've built from the early 90`s on have had factory fans.The clutch also limits how fast the fan can spin and only turns the fan at a fraction of the water pump speed, depending on engine speed and temperature. Select a Clutch Fan for: Stock or mildly modified engines; Best overall cooling ability; Applications up to 6,000 rpm; Flex fans don't use a clutch and therefore operate at 100 percent of ...These tests established that a bottom-feeder stock, no-clutch, mechanical fan robs about as much as 50 hp on the top-end (no bull). Even the best steel-bladed flex-fan still costs upwards of 20 hp.Basically, how it works is that when the engine is cold, the fan turns MUCH slower than the water pump. As the engine heats up, the warmer air flowing through the radiator heats up a small bi-metal thermostatic element on the front of the fan clutch, which engages the clutch to make the fan turn faster.If the fan has a thermal clutch (flex blades or not), when the clutch disengages, there is almost no drag on the engine from the fan (i.e. anytime the air coming through the back of the radiator is cool enough to disengage the clutch -- as it most likely would have been in Forest's case, or almost anytime you are moving forward at speed).We had a 2006 TBSS on the dyno this week that we had previously tuned in the fall. It was hot as hell in the dyno room and we still picked up 21 rwhp and 29ftlbs of torque with a PWM fan and powerbond underdrive pulley ... Other than that, e-fans are not as reliable and do not cool as well as a factory engine driven clutch fan. (aftermarket ...Jun 27, 2007 · I'd say clutch fan would be my last choice, unless you have heating problems. Flex fan is the easiest/cheapest/most reliable. If that doesn't get the job done, or if you're concerned with that last 2hp, then skip past the clutch fan and just get a good electric fan setup. [email protected] 19" Heavy Duty Stainless Steel Standard Rotation Flex Fan, Chrome Hub. Product details. Remote Filter Mount Accessories. Remote Filter Mounts. Cooling Pans. Cooling Pan Accessories. Fan Clutches. Performance Fuel Pumps.May 30, 2019 · I kinda cringe everytime I see a mustang or another vehicle with an engine driven fan and no shroud. The shroud is there to direct the air through the radiator. My 96' jeep 4.0 had the top section of the fan shroud missing above the clutch fan. When I re-attached the top section, I actually noticed an improvement in my coolant temperature. Changed the fan to a stock clutch fan-no more problems. Flex fans are junk. Keep the stock clutch fan or install electric fans. The electric fans don't draw enough power to hurt your HP. lsejlowe Premium Member Joined Jan 1, 2004 10,261 Posts #3 · Apr 29, 2009Made the throttle response so much better. "16. It takes between 10 and 70 hp to drive the cooling fan, so cooling system maintenance can have a significant effect on fuel economy. Replacing the stock clutch fan with a Flex-a-lite twin electric fan setup is said to recover 27 hp and increase fuel mileage by 6%."The fixed fans and flex fans were inferior to the clutch fan. Electric fans have the advantage of being able to cool the engine after it is shut down, but aren't likely to cool as well as a properly set up clutch fan. Remember that the electric fans are designed for today's small aluminum engines, not for the old large cast iron engines.Take a look at the huge fan shroud on our test F-150 with the 4.6L V-8. See all 22 photos. Sam started the assembly by using a drill to screw the thermostat onto the fan mold. From the Driver Seat ...Electric radiator fan conversion kits well my roommate has a 240sx and is claiming 40 hp gain from a hot air intake and a eclectic fans. i have my doubts if he is gaining anything before i go out and buy a electric fan and hot air intake please help me with a goo:waytogo:d decisionsBlack Magic electric fan: 494 hp Thermal clutch fan: 487 hp Nonthermal clutch fan: 485 hp Heavy duty thermal clutch fan: 476 hp High performance flex fan: 476 hp Stock four blade fan: 473 hp Low profile flex fan: 466 hp One piece plastic flex fan: 460 hp OE replacement six blade rigid fan: 449 hpJun 13, 2013 · 1 - Solid fan 2 - Clutch fan w/ solid blades 3 - Flex fan Electric fans can be anywhere but generally poor unless you have a very capable fan and a radiator / engine compartment big enough to fit them. Unfortunately, that list also shows which eats the most power. Jul 02, 2022 · Clutch fans are more durable and can handle more heat than flex fans, making them a better option for vehicles that frequently tow or carry heavy loads. Flex fans, on the other hand, are more affordable and easier to install than clutch fans. Ultimately, the best fan for your vehicle depends on your specific needs and driving habits. Pro - loud scream of stock fan is gone along with no more drag on the motor Pro - A/C does seem cooler Pro - temps stay around 192 consistently and a little higher with A/C and at higher rpm Pro - fairly easy install if you have some mechanical experience and some wiring experience. Con - Fan clutch bolt was an #$%^&# to get offDec 28, 2009 · there are more then one type of clutch fan,, thermal and non thermal,, non thermal is useless if you have a/c or hot weather,, a well shrould'd rad fan with thermal clutch can actualy over spin engine rpm , the trick is to have the fan properly shrould'd ,, so it see's the air temp from the rad,, thermal clutches have a temp senceing spring on the rad side of the clutch , this spring controls ... Flex fans work like clutches the fan blades will actual straighten out at speed, so there is still loss but not the 20 to 40 hp. Electric is the way to go for cool HP. i would recommend a switch so on a cruise you can turn it off because it is not doing anything at speed. Good luck and cool runnings.... 66coupe289 Registered Joined Sep 14, 2001This dual electric fan kit fits 2003-2009 Dodge Ram trucks equipped with the 5.9-liter or the 6.7-liter Cummins. With this, users can recover up to 27 horsepower and boost fuel economy by up to 6 percent by replacing the stock clutch fan assembly with this dual electric fan system. It features two 15-inch S-Blade electric fans and a Flex-A-Lite ...240 clutch fan vs. electric fan performance & modifications Turbobricks Forums > Mechanical ... No questions asked. If that is no performance advantage then why not put a noisy flex fan on that pulls even more hp. I will cool better 06-18-2009, 01:04 PM ... Forget that I beat it on the dyno for about 4 hours straight, pulling to 7600rpm with ...Actually, because of the blade pitch, the clutch fan will move MUCH more air than a flex fan at any given RPM, WHEN THE CLUTCH IS ENGAGED. When it's not engaged, it obviously moves less air and requires less power. ... does a flex fan really only take 2HP more than an electric fan setup? has anybody seen dyno sheets to prove this cuz if thats ...As engine coolant temperature rises within the radiator, the air passing through the radiator heats the spring coil on the fan clutch Since the electric fan only runs when needed, less noise is made i want it to run when it needs to not contantly running nor do i want a switch This is the new harness that many customers have been asking about ... A standard clutch runs at around 60%-70% of engine speed so that's around 5700-6700 engine RPM that the fan is safe for. What aggravates me is that Summit carries several heavy duty clutches (which run at 80%-90% of engine speed) but only standard duty fans. I guess those clutches have to be used with a factory fan from an RV or HD truck. RApr 06, 2020 · These tests established that a bottom-feeder stock, no-clutch, mechanical fan robs about as much as 50 hp on the top-end (no bull). Even the best steel-bladed flex-fan still costs upwards of 20 hp. May 07, 2004 · 46. 48. Covington. 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. In this video, I finally put the myth to rest as to whether a clutch style/mechanical radiator fan sucks power from your engine! Enjoy!Injection Connection, ...Apr 12, 2010 · Nick, I'm not a big fan(no pun intended!) of the flex fans, although the wide blade variety might work fine. I use the stock rigid fan with a clutch, works well. I don't have the serpentine set-up so I'm no help there, although if the w/p is reverse rotation one would think the fan would be as well. Good luck, Alex Basically, how it works is that when the engine is cold, the fan turns MUCH slower than the water pump. As the engine heats up, the warmer air flowing through the radiator heats up a small bi-metal thermostatic element on the front of the fan clutch, which engages the clutch to make the fan turn faster.It rarely fails, although it can age and the clutch may not work as well after 8-10 years. Until then, the clutch keeps the fan from over spinning based on temperature it reads. The primary benefit of an electric fan is that it theoretically removes the load from the engine, especially because it can be configured to only come on when needed.With the E-fans, it blows ice cold all the time no matter whether I am doing 60mph, or driving 5mph thru a parking lot. To be honest, I probably could have achieved the same end results by leaving the clutch fan on and just adding a thin pusher fan like a flex a lite or something between the condensor and the front grill.Sep 01, 2003 · That's why the fan clutch improves fuel mileage, it reduces drag on the engine when it's free wheeling at travel speeds. The switch from a 3 bladed fan to 6 or the flex fan shouldn't have made any difference at highway speeds, there's supposed to be enough air flow to handle the cooling. Jun 13, 2013 · 1 - Solid fan 2 - Clutch fan w/ solid blades 3 - Flex fan Electric fans can be anywhere but generally poor unless you have a very capable fan and a radiator / engine compartment big enough to fit them. Unfortunately, that list also shows which eats the most power. May 07, 2004 · 46. 48. Covington. 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. Jun 11, 2006 · Clutch fans have a similar limitation, that is whey flex fans with bimetallic thermostats were developed. Ultimately, electric fans are the best solution as turning on the fan when necessary. There are a lot of variables for airflow with fans. In general more blades are better. The amount of airflow also depends on how close the fan is to the ... Sep 08, 2015 · Clutch fan pulls well at idle, then clutches and floats/freewheels when road speed is high enough to provide the needed air flow or engine rpm goes higher than the fan's peak efficiency rpm. The fixed flex fans just plain suck, don't pull enough air and eat an alarming amount of horsepower depending on the exact model, all are bad but some are really bad (45hp+). Electric fans will use the least amount of HP, but often just can't pull enough air....often a problem when a relatively small ... The fan clutch uses a viscous fl uid for cooling fan engagement, while a thermal spring operates valving controlling fl uid fl ow and fan engagement. As engine heat drops, so does the fan’s engagement to lower parasitic drag. As good as this fan clutch worked for the era, the fan only activated as fast as the engine RPM allowed. [email protected] Ram Year. 2003. Engine. 5.7 hemi. 3rd gens did not come with electric fans EXCEPT for the A/C fan. Some 4th gens did from the factory. It is not a retrofittable plug and play to a 3rd gen. Two most popular eelctric fan conversions for 3rd gens are flexalite 180's and early 90's 3.8 Taurus fan. May 10, 2018.Came across a HotRod dyno shop with Frieberg from Hot Rod magazine as the host. He was testing fans and the factory fluid coupled fan used the least while the large plastic flex fan used the most your light weight aluminum fan was in the middle but it still sucked up 6.3 more horsepower than the clutch fan. Engine Masters TV with Dave FriebergJul 02, 2022 · Clutch fans are more durable and can handle more heat than flex fans, making them a better option for vehicles that frequently tow or carry heavy loads. Flex fans, on the other hand, are more affordable and easier to install than clutch fans. Ultimately, the best fan for your vehicle depends on your specific needs and driving habits. Apr 16, 2010 · Re: Electric fan debate. Quote. Postby car nut » Fri Jul 30, 2010 1:33 pm. An electric fan is a downgrade over a mechanical fan. The only advantage is freeing up 1%-2% more power. Otherwise, and electric fan will never be as reliable, nor will it pull as much as a mechanical fan. Top. Jul 31, 2003 · 227 Posts. #3 · Jul 31, 2003. Over on an A/C board, they seem to recoment staying away from the flex fan and sticking with the stock unit, or even upgrade to a newer stock unit with more blades (I think 96+ has a better electric fan on the XJs with a bunch more blades than the standard 5 (?) blade electric (was that Kingsize that pointed this out? Apr 03, 2020 · Clutch fans are the right choice for stock or mildly modified engines. They will adequately cool the engine. Just be sure to use the fan and clutch designed for your application. Using the wrong parts could result in poor cooling, excessive noise, reduced fuel economy, and/or fan clutch failure. For high rpm use, flex fans are considered an ... In this video, I finally put the myth to rest as to whether a clutch style/mechanical radiator fan sucks power from your engine! Enjoy!Injection Connection, ... See full list on carsupercare.com May 25, 2008 · The clutch fan blades typically are similar to a fixed fan's blades — the difference is that the clutch slows the rotation at high engine speeds as a way to conserve horsepower. The clutch fan does not improve cooling vs. a fixed fan with the same blade count and pitch — what it does is enable using a more aggressive fan profile without ... 1 - Max cooling - large aftermarket fixed fan with a good full shroud and a big multi-core radiator. 2 - Very good cooling - large HD clutch fan, with a good full shroud and big radiator. 3 - Electric high capacity - Very large dual electric fan and buy radiator to fit fan, adapt to truck to include relayed power.Engine dyno No fan: 349/406.9. Clutch Fan: 335/400. Plastic flex fan: 325.1/388.3. Aluminum Fan: 328.7/394.9. Fixed steel OEM fan: 318.6/388 . Last edited: May 29, 2019. ... The shroud is there to direct the air through the radiator. My 96' jeep 4.0 had the top section of the fan shroud missing above the clutch fan. When I re-attached the top ...Clutch Fans have fixed blades. They require a coupler to engage and disengage the fan. This coupler is called the Fan Clutch. Flex Fans do not need a clutch. At high rpm, the blades "flatten out." This achieves the same function as disengaging the fan. However, flex fans require a Fan Spacer.May 25, 2008 · The clutch fan blades typically are similar to a fixed fan's blades — the difference is that the clutch slows the rotation at high engine speeds as a way to conserve horsepower. The clutch fan does not improve cooling vs. a fixed fan with the same blade count and pitch — what it does is enable using a more aggressive fan profile without ... 2020 gt500 conversion kit May 07, 2004 · 46. 48. Covington. 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. Jun 27, 2007 · I'd say clutch fan would be my last choice, unless you have heating problems. Flex fan is the easiest/cheapest/most reliable. If that doesn't get the job done, or if you're concerned with that last 2hp, then skip past the clutch fan and just get a good electric fan setup. On the dyno I made 1hp more than with the stock fan, but lost 3tq. Yes, a real dyno, the same dyno, and yes, it corrects for weather. At the track I saw no performance gains. None. The car does sound a lot better without the Clutch fan whirrin' under there. I got mine slightly used for $75 2 years ago and it still works flawlessly.Mar 18, 2010 · mopar performance tested all available V8 fans and the viscous drive asymmetric 5 blade MP unit won. 16 hp gain over no clutch standard and flex fans. flex fans might cut wind resistance but not rotating mass which eats power. the 5 blade mp fan fits all stock big block (and probably most 57-61 V8s) 60/61 mopars and cools very well. 2-Blade 18" Steel Fan by Hendren Racing Engines--Flat Black. $52.75. Current stock: 11. Qty: Save. Add to Bag. 18" 2-Blade Steel Fan with 32 degrees pitch. Dyno testing proves that it requires the least amount of power to drive the fan while also providing better cooling in most situations. It is best when used in conjunction with a fan shroud.240 clutch fan vs. electric fan performance & modifications Turbobricks Forums > Mechanical ... No questions asked. If that is no performance advantage then why not put a noisy flex fan on that pulls even more hp. I will cool better 06-18-2009, 01:04 PM ... Forget that I beat it on the dyno for about 4 hours straight, pulling to 7600rpm with ...Take a look at the huge fan shroud on our test F-150 with the 4.6L V-8. See all 22 photos. Sam started the assembly by using a drill to screw the thermostat onto the fan mold. From the Driver Seat ...Jul 31, 2003 · 227 Posts. #3 · Jul 31, 2003. Over on an A/C board, they seem to recoment staying away from the flex fan and sticking with the stock unit, or even upgrade to a newer stock unit with more blades (I think 96+ has a better electric fan on the XJs with a bunch more blades than the standard 5 (?) blade electric (was that Kingsize that pointed this out? Aug 09, 2012 · The clutch fan draws power from the engine due to the added load.... The electric fan saves power due to no load on the engine.... Clutch fans are better because they only apply a load at idle or low speed and don't require wiring... Electric fans save power but add weight and require a lot of wiring... Aug 8, 2012. Aug 09, 2012 · The clutch fan draws power from the engine due to the added load.... The electric fan saves power due to no load on the engine.... Clutch fans are better because they only apply a load at idle or low speed and don't require wiring... Electric fans save power but add weight and require a lot of wiring... Aug 8, 2012. The V2 with Fan kit is $1240. The CAI kit is $65. We highly recommend the V2 with Fan kit if you are serious about thoroughly squashing overheating and that irritating engine fan. This kit is THE CURE for those ills and is well worth it once you see all the benefits that come about after it is installed.Sep 27, 2004 · I ran a flex fan for years and what bugged me more than anything was the noise. I ran 3" exhaust with cherry bombs, and the fan was still louder than the exhaust. I also drag race, and have read that they have a habit of exploding at high rpm, so I finally switched to a stock type clutch fan for less drag at high speeds. www.Flex-A-Lite.com. This spacer/adapter replaces the fan clutch and hub by simply screwing onto the water pump. The fan bolts directly to the new spacer adapter. The motion of the fan tightens ...Sep 27, 2004 · I ran a flex fan for years and what bugged me more than anything was the noise. I ran 3" exhaust with cherry bombs, and the fan was still louder than the exhaust. I also drag race, and have read that they have a habit of exploding at high rpm, so I finally switched to a stock type clutch fan for less drag at high speeds. Pro - loud scream of stock fan is gone along with no more drag on the motor Pro - A/C does seem cooler Pro - temps stay around 192 consistently and a little higher with A/C and at higher rpm Pro - fairly easy install if you have some mechanical experience and some wiring experience. Con - Fan clutch bolt was an #$%^&# to get offBlack Magic electric fan: 494 hp Thermal clutch fan: 487 hp Nonthermal clutch fan: 485 hp Heavy duty thermal clutch fan: 476 hp High performance flex fan: 476 hp Stock four blade fan: 473 hp Low profile flex fan: 466 hp One piece plastic flex fan: 460 hp OE replacement six blade rigid fan: 449 hpThe rpm-activated clutch fan outperformed all the flex fans tested but was inferior to the fixed-blade O.E. fan below 3,500 rpm. In conclusion, the best power can still be made with no fan at all. Short of this, a thermo-controlled clutch fan is the best choice for optimum power and cooling capacity. CHPMade the throttle response so much better. "16. It takes between 10 and 70 hp to drive the cooling fan, so cooling system maintenance can have a significant effect on fuel economy. Replacing the stock clutch fan with a Flex-a-lite twin electric fan setup is said to recover 27 hp and increase fuel mileage by 6%."Jun 18, 2009 · The Volvo mechanical fan has a slip clutch so it reduces parasitic loss. The flex fans go flat as they are revved up for less hp loss. They are also much lighter than the clutch type mechanical fans so they are less load on the engine. Use what you want. It's easy to chose either way and they both work. 240 clutch fan vs. electric fan performance & modifications Turbobricks Forums > Mechanical ... No questions asked. If that is no performance advantage then why not put a noisy flex fan on that pulls even more hp. I will cool better 06-18-2009, 01:04 PM ... Forget that I beat it on the dyno for about 4 hours straight, pulling to 7600rpm with ...Sep 08, 2015 · Clutch fan pulls well at idle, then clutches and floats/freewheels when road speed is high enough to provide the needed air flow or engine rpm goes higher than the fan's peak efficiency rpm. The fixed flex fans just plain suck, don't pull enough air and eat an alarming amount of horsepower depending on the exact model, all are bad but some are really bad (45hp+). Electric fans will use the least amount of HP, but often just can't pull enough air....often a problem when a relatively small ... Jul 22, 2009 · My Sierra came with two electric fans, side by side. The rad is wide but short, so two fans are needed to cover the rad properly. I had a 1982 Mazda B2000 pu that came with a basic fan, not flex or clutch. I took the fan off and installed a electric fan and the fan would turn on maybe 1% of the time. I saved a bit of fuel by using the electric fan. Standard Fan -Pros over Clutch - Nothing much, cheaper maybe. -Cons over Clutch - Direct drive from the engine. From idle to 6000rpm. More load on the engine = robs more power. Clutch -Pros over Std - Fan drive is varied by engine temp (cooler the temps, more the fan 'free wheels'. Hotter it tightens up).Ram Year. 2003. Engine. 5.7 hemi. 3rd gens did not come with electric fans EXCEPT for the A/C fan. Some 4th gens did from the factory. It is not a retrofittable plug and play to a 3rd gen. Two most popular eelctric fan conversions for 3rd gens are flexalite 180's and early 90's 3.8 Taurus fan. May 10, 2018.May 06, 2012 · Sigh, this topic again. Electric fans FTW. Engine driven fans suck. But go ahead and install that flex fan and see for yourself how much they suck. Flex fans rob HP 100% of the time. Clutch fans rob HP 100% of the time too. Only clutch fans use less HP when idling but they still spin the fan 100% of the time even when not needed. Aug 20, 2018 · If the fan spins more than three times, you may have a bad fan clutch. If the fan doesn’t spin at all, the bearing may be seized. Wiggle the fan. Try moving the fan forward and backward. If it wobbles more than a quarter-inch or you feel it clicking, this may indicate a worn bearing. Inspect for leaks. It rarely fails, although it can age and the clutch may not work as well after 8-10 years. Until then, the clutch keeps the fan from over spinning based on temperature it reads. The primary benefit of an electric fan is that it theoretically removes the load from the engine, especially because it can be configured to only come on when needed.It rarely fails, although it can age and the clutch may not work as well after 8-10 years. Until then, the clutch keeps the fan from over spinning based on temperature it reads. The primary benefit of an electric fan is that it theoretically removes the load from the engine, especially because it can be configured to only come on when needed.I dyno'd my Sammy at 57hp* of a rated 64 (EFI model) with factory old clutch fan. Which between drivetrain loss and parasitics losses seems pretty good. So I'd either leave it stock or go e-fan personally. Like AxlesUp said, the fan often isn't needed a lot of the time.Re: Electric fan debate. Quote. Postby car nut » Fri Jul 30, 2010 1:33 pm. An electric fan is a downgrade over a mechanical fan. The only advantage is freeing up 1%-2% more power. Otherwise, and electric fan will never be as reliable, nor will it pull as much as a mechanical fan. Top.Apr 19, 2012 · In addition I have seen multiple dyno tests where a significant amount of power was freed up at the wheels. There have been many rag tests over then years that have shown that the most efficient (parasitic losses) engine driven fans are of the viscous clutch type. I have seen 20 to 40 fwhp HP from worst to best. A standard clutch runs at around 60%-70% of engine speed so that's around 5700-6700 engine RPM that the fan is safe for. What aggravates me is that Summit carries several heavy duty clutches (which run at 80%-90% of engine speed) but only standard duty fans. I guess those clutches have to be used with a factory fan from an RV or HD truck. RDaves assertions are indisputable. If you compare CFM to CFM, there will not be any performance gain by using an electric fan. The only way the electric fan could be more efficient is if it were able to more accurately tune the air flow to the needs of the engine minute by minute.That would also assume that the OEM fan is substantially over cooling the engine most of the time.In addition, the clutch is never completely disengaged, so the fan is always turning at about 30 percent of the water-pump speed. Flex fans spin at a 1:1 ratio of the water pump, but that's still too limiting. Thus, both clutch-driven and mechanical fans are suited for mildly modified engines and should not be used for extreme performance builds.Dec 16, 2014 · The fixed fans and flex fans were inferior to the clutch fan. Electric fans have the advantage of being able to cool the engine after it is shut down, but aren't likely to cool as well as a properly set up clutch fan. Remember that the electric fans are designed for today's small aluminum engines, not for the old large cast iron engines. Apr 06, 2020 · These tests established that a bottom-feeder stock, no-clutch, mechanical fan robs about as much as 50 hp on the top-end (no bull). Even the best steel-bladed flex-fan still costs upwards of 20 hp. Apr 27, 2018 · This dual electric fan kit fits 2003-2009 Dodge Ram trucks equipped with the 5.9-liter or the 6.7-liter Cummins. With this, users can recover up to 27 horsepower and boost fuel economy by up to 6 percent by replacing the stock clutch fan assembly with this dual electric fan system. It features two 15-inch S-Blade electric fans and a Flex-A-Lite ... May 25, 2008 · The clutch fan blades typically are similar to a fixed fan's blades — the difference is that the clutch slows the rotation at high engine speeds as a way to conserve horsepower. The clutch fan does not improve cooling vs. a fixed fan with the same blade count and pitch — what it does is enable using a more aggressive fan profile without ... The V2 with Fan kit is $1240. The CAI kit is $65. We highly recommend the V2 with Fan kit if you are serious about thoroughly squashing overheating and that irritating engine fan. This kit is THE CURE for those ills and is well worth it once you see all the benefits that come about after it is installed.A Flex-Fan w/Billet Aluminum Spacer or a Black Magic Electric Fan: The Flex-Fan has fan blades that flatten out at higher RPM to reduce fan drag. At lower RPM, the blades return to their original shape to pull the maximum amount of air through the radiator and fan shroud. It is important to understand that a Flex-Fan is most efficient when it ...Apr 19, 2012 · In addition I have seen multiple dyno tests where a significant amount of power was freed up at the wheels. There have been many rag tests over then years that have shown that the most efficient (parasitic losses) engine driven fans are of the viscous clutch type. I have seen 20 to 40 fwhp HP from worst to best. Apr 03, 2020 · Clutch fans are the right choice for stock or mildly modified engines. They will adequately cool the engine. Just be sure to use the fan and clutch designed for your application. Using the wrong parts could result in poor cooling, excessive noise, reduced fuel economy, and/or fan clutch failure. For high rpm use, flex fans are considered an ... The standard fan runs all the time, it comes on fully not only for coolant temperature, but also for charge air temp. If you need to put on enough electric fans flow the same amount of air that the standard fan does, and you have to put on a larger alternator to make it work, then I can see no possible way that you could gain HP.The rpm-activated clutch fan outperformed all the flex fans tested but was inferior to the fixed-blade O.E. fan below 3,500 rpm. In conclusion, the best power can still be made with no fan at all. Short of this, a thermo-controlled clutch fan is the best choice for optimum power and cooling capacity. CHP The clutch fan does not improve cooling vs. a fixed fan with the same blade count and pitch — what it does is enable using a more aggressive fan profile without costing as much HP to drive it at high speeds. So your typical clutch fan has more or bigger blades, possibly with a more aggressive pitch, than a fixed fan.Dec 18, 2014 · Opinion: 1. Flex fan is dangerous. 2. Electric fan is inefficient: Belt drive a generator to charge a battery and/or provide current to run an electric motor to turn a fan. 3. Belt drive a fan. #3 is the way to go unless belt drive of the fan is impractical as--for example--is the case on transverse-mounted engines. Dec 18, 2014 · Opinion: 1. Flex fan is dangerous. 2. Electric fan is inefficient: Belt drive a generator to charge a battery and/or provide current to run an electric motor to turn a fan. 3. Belt drive a fan. #3 is the way to go unless belt drive of the fan is impractical as--for example--is the case on transverse-mounted engines. well my roommate has a 240sx and is claiming 40 hp gain from a hot air intake and a eclectic fans. i have my doubts if he is gaining anything before i go out and buy a electric fan and hot air intake please help me with a goo:waytogo:d decisionsI have a dual 1 1/4" tube aluminum rad & stock shroud. It had an engine driven flex fan before and seems better with the clutch fan - definitely quieter. I drove about 40 miles with the fan just free-wheeling when the clutch went bad and temperature was fine at 50 mp, but would start to get hot when slowed down and stopped at a cross roads.Take a look at the huge fan shroud on our test F-150 with the 4.6L V-8. See all 22 photos. Sam started the assembly by using a drill to screw the thermostat onto the fan mold. From the Driver Seat ...May 25, 2008 · Depends on the pitch of the blades, temperature range of the clutch thermostat, diameter, blade count, all sorts of factors. Usually the flex fans have a more aggressive pitch, meaning they move more air at low engine speeds, then they flatten out at high engine speeds. See full list on carsupercare.com Mar 18, 2010 · mopar performance tested all available V8 fans and the viscous drive asymmetric 5 blade MP unit won. 16 hp gain over no clutch standard and flex fans. flex fans might cut wind resistance but not rotating mass which eats power. the 5 blade mp fan fits all stock big block (and probably most 57-61 V8s) 60/61 mopars and cools very well. www.Flex-A-Lite.com. This spacer/adapter replaces the fan clutch and hub by simply screwing onto the water pump. The fan bolts directly to the new spacer adapter. The motion of the fan tightens ...Jul 29, 2014 · 575 Posts. #3 · Jul 29, 2014. Only show this user. When I was much yonger-my reassoning towards a flex fan was-less mass/drag w/ higher RPM. However these Jeep inline 4 & 6 cyl engines are no screamers. The fan clutch works better-alowing a faster warm-up, and by engaging hydralicly and according to temperature will keep your engine at correct ... Flex fans vs. clutch fans vs electric fans. Jump to Latest Follow 21 - 24 of 24 Posts. Prev ... Car Craft mag did a big dyno test on a 496HP SBC on a large selection of fans....the worst offender, the Flex-a-Lite replacement for the GM 6-blade rigid fan, lost a whopping 47 hp!! Archived on the Cleveland engines forum... Cleveland Photos:May 07, 2004 · 46. 48. Covington. 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. May 30, 2019 · I kinda cringe everytime I see a mustang or another vehicle with an engine driven fan and no shroud. The shroud is there to direct the air through the radiator. My 96' jeep 4.0 had the top section of the fan shroud missing above the clutch fan. When I re-attached the top section, I actually noticed an improvement in my coolant temperature. Sep 20, 2018 · Pros: Very little parasitic loss. While any loss is considered a con, electric fans create far less than a mechanical fan resulting in increased power and better fuel economy. Ability to completely disengage. Allows for faster engine warm-up. Only draws power when it needs to cool. Ability to efficiently cool at low engine RPMs. Pro - loud scream of stock fan is gone along with no more drag on the motor Pro - A/C does seem cooler Pro - temps stay around 192 consistently and a little higher with A/C and at higher rpm Pro - fairly easy install if you have some mechanical experience and some wiring experience. Con - Fan clutch bolt was an #$%^&# to get offJul 05, 2014 · Flex fans will cost you in efficiency. The fan is typically not even needed when going down the road so the clutch uncouples it saving you hp wasted to spin the fan. Guy on one of the Corvette forums tried six hubs and eight fans over 200 dyno runs with his engine. Clutch fan when uncoupled cost 2hp compared to no fan at all. I have a dual 1 1/4" tube aluminum rad & stock shroud. It had an engine driven flex fan before and seems better with the clutch fan - definitely quieter. I drove about 40 miles with the fan just free-wheeling when the clutch went bad and temperature was fine at 50 mp, but would start to get hot when slowed down and stopped at a cross roads. I dyno'd my Sammy at 57hp* of a rated 64 (EFI model) with factory old clutch fan. Which between drivetrain loss and parasitics losses seems pretty good. So I'd either leave it stock or go e-fan personally. Like AxlesUp said, the fan often isn't needed a lot of the time.2020 gt500 conversion kit Aug 09, 2012 · The clutch fan draws power from the engine due to the added load.... The electric fan saves power due to no load on the engine.... Clutch fans are better because they only apply a load at idle or low speed and don't require wiring... Electric fans save power but add weight and require a lot of wiring... Aug 8, 2012. No fan = 496hp Electric = 494hp Thermal clutch = 487hp Nonthermal clutch = 485hp HD thermal = 476hp HP flex fan = 476hp Stock 4 blade = 473hp Low-profile flex = 466hp One piece plastic flex = 460hp OE replacement 6 blade = 449hpStandard Fan -Pros over Clutch - Nothing much, cheaper maybe. -Cons over Clutch - Direct drive from the engine. From idle to 6000rpm. More load on the engine = robs more power. Clutch -Pros over Std - Fan drive is varied by engine temp (cooler the temps, more the fan 'free wheels'. Hotter it tightens up).Engine dyno No fan: 349/406.9. Clutch Fan: 335/400. Plastic flex fan: 325.1/388.3. Aluminum Fan: 328.7/394.9. Fixed steel OEM fan: 318.6/388 . Last edited: May 29, 2019. ... The shroud is there to direct the air through the radiator. My 96' jeep 4.0 had the top section of the fan shroud missing above the clutch fan. When I re-attached the top ...If the fan has a thermal clutch (flex blades or not), when the clutch disengages, there is almost no drag on the engine from the fan (i.e. anytime the air coming through the back of the radiator is cool enough to disengage the clutch -- as it most likely would have been in Forest's case, or almost anytime you are moving forward at speed).Dec 18, 2014 · Opinion: 1. Flex fan is dangerous. 2. Electric fan is inefficient: Belt drive a generator to charge a battery and/or provide current to run an electric motor to turn a fan. 3. Belt drive a fan. #3 is the way to go unless belt drive of the fan is impractical as--for example--is the case on transverse-mounted engines. Apr 19, 2012 · In addition I have seen multiple dyno tests where a significant amount of power was freed up at the wheels. There have been many rag tests over then years that have shown that the most efficient (parasitic losses) engine driven fans are of the viscous clutch type. I have seen 20 to 40 fwhp HP from worst to best. Re: Electric fan debate. Quote. Postby car nut » Fri Jul 30, 2010 1:33 pm. An electric fan is a downgrade over a mechanical fan. The only advantage is freeing up 1%-2% more power. Otherwise, and electric fan will never be as reliable, nor will it pull as much as a mechanical fan. Top.Re: Electric fan debate. Quote. Postby car nut » Fri Jul 30, 2010 1:33 pm. An electric fan is a downgrade over a mechanical fan. The only advantage is freeing up 1%-2% more power. Otherwise, and electric fan will never be as reliable, nor will it pull as much as a mechanical fan. Top.The clutch also limits how fast the fan can spin and only turns the fan at a fraction of the water pump speed, depending on engine speed and temperature. Select a Clutch Fan for: Stock or mildly modified engines; Best overall cooling ability; Applications up to 6,000 rpm; Flex fans don't use a clutch and therefore operate at 100 percent of ... why are night clubs so expensivefishman loudbox mini bluetooth manualtwigs alaskan gifts