# clutch fan



## jbs (Jul 23, 2012)

have a 68 GTO which had later water pump on it. put correct style back on now clutch fan sits outside of shroud car had had flex fan from factory. old owner put clutch fan on .


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## torrid red sap (Sep 27, 2014)

Clutching fan Is the way to go, gm makes spacer to move fan closer, needs to be just inside shroud for proper cooling


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## jbs (Jul 23, 2012)

thanks have spacer that come with flex fan


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## torrid red sap (Sep 27, 2014)

various spacers were available depending on application, AC equipped ETC. anyway, point is relationship between shroud and fan need to be correct, do u have correct shroud? jus my 2 cents, have owned many Pontiacs in my time.(65 gto,70 gto,73 TA,81 TA,68 tempest sprint, currently 05 gto) anyway good luck.


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## jbs (Jul 23, 2012)

yes have correct shroud. I don't think I can use spacer that was for flex fan ?


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## allpawl66 (May 9, 2008)

Lose the clutch fan , put the flex back on 100% air pulled @ idle & low rpm / clutch fan is not / thermo. in new clutch will not keep cool unless adjusted comes set for new engines @ higher temps.


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## chuckha62 (Apr 5, 2010)

Whoa... Don't ditch the clutch fan just yet. There's a reason GM used them. They work! They put many millions of dollars in the development of these cars and had to carry a warranty on them. The makers of the aftermarket flex fans will not carry any warranty on them whatsoever. A properly functioning and properly positioned clutch fan is the correct way to go here. The fan blades should be bisected by the edge of the shroud. The fan clutch is available in different lengths to achieve this. A spacer is not the answer with the clutch, as it is with a flex fan.


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## geeteeohguy (Feb 2, 2008)

Do NOT use a spacer with a clutch fan unless you want your water pump to fail early on. A clutch fan is much too heavy to be mounted way out there at the end of a spacer, and will destroy the water pump bearing and possibly throw the fan. I have seen it happen. Use a correct fan clutch or the flex fan of your choice. I am runnning a clutch fan on the '65 (works fine) and a junkyard '69 Cadillac 7 blade flex fan on my '67, and it's dead silent and works as well as the clutch fan does. I have had bad luck with the noisy and blade-throwing aftermarket stainless steel and fiberglass flex fans.


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## Rukee (Feb 8, 2007)

I agree, stick with what Pontiac gave it, the correct clutch fan. It cools when it's suppose to and you get a few extra ponies out of it too.


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## rickm (Feb 8, 2012)

the split grill design on gtos looks great but, its a chore keeping the motor at a desirable temperature. to each his own on the fan clutch topic. whatever works best for your motor. I have one question. when drag racing a Pontiac motor, what do most racers use ?


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## chuckha62 (Apr 5, 2010)

rickm said:


> the split grill design on gtos looks great but, its a chore keeping the motor at a desirable temperature. to each his own on the fan clutch topic. whatever works best for your motor. I have one question. when drag racing a Pontiac motor, what do most racers use ?


I'm betting they use a flex fan due to it's light weight and the short run times.


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## torrid red sap (Sep 27, 2014)

Ditto, Clutch Fans work ,GM new what they were doing, el cheepo fans can loose blades at high rpm,dont re invent the wheel!!!!!


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## jbs (Jul 23, 2012)

spoke with president of GTO club and he said to use Hayden clutch gave me part # so I will see.


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## 666bbl (Apr 13, 2014)

rickm said:


> the split grill design on gtos looks great but, its a chore keeping the motor at a desirable temperature. to each his own on the fan clutch topic. whatever works best for your motor. I have one question. when drag racing a Pontiac motor, *what do most racers use ?*


Serious cars use electric fans and pumps. I used a stock pump, plastic 1pc flex fan, both driven by a Moroso electric motor. It was a .100 over 454 with 14:1 pistons and roller cam, everything painted semi-flat black. I had to do my burnout and pre-stage with the fan off to get heat in the system, turn it on and stage which would then have the engine at 180deg. By the end of the run it dropped (!) to 160. I did spend some hours making sure that all the passages from the block, heads and intake were matched and clear of casting flash. 

Back on topic, clutch fan? I'm in. The right choice for a driver.


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