Will A Flex Fan Cool Better ?????????
Melting Slicks
Joined: May 2003
Posts: 2,078
Likes: 283
From: Dyersburg TN
flex fan
The fan's job is to move air through the radiator at low speeds. At higher speeds the air moves on it's own. Once you are at speed, a regular fan is not needed as much and can provide drag. As such factory fans have clutches designed to slip. Flex fans provide the same thing by flatting out at high RPM so as not to be a drag on HP.
Having said all that, just because a fan is a flex fan does not make for better cooling. Most modern cars use electric fans. Come on when needed, no drag on engine.
None of this matters BTW if radiator or other parts are bad. All must work together.
Having said all that, just because a fan is a flex fan does not make for better cooling. Most modern cars use electric fans. Come on when needed, no drag on engine.
None of this matters BTW if radiator or other parts are bad. All must work together.
Thread Starter
Acct suspended by request 19 April 2011
Joined: Jul 2009
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From: La Porte In
I am running warm days at 60 mph at 210. Drop down to 45 for a couple minutes drops quick to 180. Has fairly new radiator I think. Looks good inside and out. Have had the car for 2 years.
Melting Slicks
Joined: May 2003
Posts: 2,078
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From: Dyersburg TN
cooling is about water flow and air flow. has the coolant been flushed? is the raditor shroud intact. What about your spoiler? it directs air through raditor when moving. Water pump old? It all works together.
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Flex fans wont cool your engine any better than a properly set up factory system. Get the system working as it was designed rather than trying to compensate for a problem that hasn't been corrected.
Le Mans Master
Joined: Aug 2003
Posts: 7,720
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From: Chattanooga TN
Make sure all your seals are good. A C3 is a bottom cooler, you have to have the front air dam and all the foam seals around the radiator to be functioning. Also make sure the thermostat is good, radiator cap is good.
Burning Brakes
Joined: Jun 2008
Posts: 1,086
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From: Michigan
As others have mentioned, make sure you have all the seals and the air dam under the car. I don't think the flex fan provides any greater cooling over stock either. I must say though that my engine and water pump like my flex fan due to the dramatic decrease in weight over the stock steel fan and clutch.
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Melting Slicks
Joined: Sep 2004
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Stick with the stock fan, make sure your fan clutch is good. Check to make sure all seals, spoiler, fan shroud are intact/correct.
If that doesn't work you can add an electric fan. My 68 small block had the smallest rad ever put in a C3. The addition of a cheap electric fan mad a lot of difference. All you need is the fan, mounting kit, a fuse, relay, and temp swotch. Wiring instructions will come with the fan.
If that doesn't work you can add an electric fan. My 68 small block had the smallest rad ever put in a C3. The addition of a cheap electric fan mad a lot of difference. All you need is the fan, mounting kit, a fuse, relay, and temp swotch. Wiring instructions will come with the fan.
Le Mans Master
Joined: Jan 2006
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From: Butler Pa
Instructor
Joined: May 2008
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From: Indiana
The lower hose on the radiator may be collapsing at higher RPM and restricting water flow. May want to check that hose or replace it. The original hose came with a spring in it to eliminate the collapsing issue. A replacement may not have the spring because the rubber is stronger but if your is weak, old or wrong type it may be the culpret.
Team Owner
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From: Southbound
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Le Mans Master
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From: Butler Pa
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From: Reno Nevada
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My L-82 with A/C came with factory shroud with a built in electric fan. But if you don't have that, check and make sure that the bottom flap under the radiator is free and open and closes. Years ago I bought some 6 inch flex black wall trim molding and big rivited it to the chin spoiler. It was 3-4 inches closer to the ground. It was a vast improvement to cooling. because you are not allowing air under the car which created a lower pressure in the engine compartment. allowing more air to flow through the radiator the faster you go.
My 79 used to get really hot driving fast when it was over 100 degrees outside.
Race Director
Joined: Sep 2002
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From: San Diego - Deep Within The State of CONFUSION!
When I worked at the Dyno Shop, we wouldn't even redline engines with those cheap things on them. There was an incident with a flex fan losing a fin at high RPM and from then on, we outlawed them in the shop.
Team Owner
Joined: Apr 1999
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From: Reno Nevada
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Then there must have been a prob with the OEM cooling system. Flex Fans are junk, and sold by hype and market ploy only.
When I worked at the Dyno Shop, we wouldn't even redline engines with those cheap things on them. There was an incident with a flex fan losing a fin at high RPM and from then on, we outlawed them in the shop.
When I worked at the Dyno Shop, we wouldn't even redline engines with those cheap things on them. There was an incident with a flex fan losing a fin at high RPM and from then on, we outlawed them in the shop.
I even run a gearing reduced alternator larger diameter pulley because I exploded one. Right on the power master box it said to not exceed 17,000 rpm.
Race Director
Joined: Sep 2002
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From: San Diego - Deep Within The State of CONFUSION!
Melting Slicks
Joined: Oct 2002
Posts: 2,317
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From: St Louis MO
The stock fan setup works fine.
If your temperature indication is too high, get an IR temp sensing gun and check it. The reason is that the different brands of temperature sensors vary a lot from the correct curve of resistance versus temperature - this can make your gauge read too high (or too low).
If your temperature indication is too high, get an IR temp sensing gun and check it. The reason is that the different brands of temperature sensors vary a lot from the correct curve of resistance versus temperature - this can make your gauge read too high (or too low).
Melting Slicks
Joined: May 2003
Posts: 2,078
Likes: 283
From: Dyersburg TN
one more note
just remembering a upper hose I had that seperated on the inside. Outside looked fine and no leaks, inside it was a blockage. With hoses just cold or just warming up grab and see if you feel any 'soft' spots.