fryer1979

My Camaro is currently running with a OE stock clutch fan, and during extended cruising or highway trips it tends to run a bit more hot than I would like. I know than switching to electric fans would be the ultimate solution, but while other projects are currently demanding my money and attention I am considering swapping to a flex fan. I've got a brand new 3-row stock type radiator, high flow water pump, and high flow 160 degree thermostat, and I get really close to 200 degrees on the highway and sometimes over while cruising town. Would a swap to the flex fan be benificial? Or should I just wait to to the complete rebuild on this car (probably 5 years away still) when I install an aluminum radiator and electric fans? Any opinions would be welcome as I am just trying to make this car better to drive for the next few years before it is rebuilt.

Oh, the engine is a mild, carbed 350. The trans is an externally cooled TH-350. It currently has 3.08 gears, but I am switching to 3.73.

Thanks guys.

paul_huryk

Flex fan is not worth the effort. Save up and buy electric fan(s).

8t2 z-chev

A flex fan will actually help a lot with cooling on the
highway (clutch fans freewheel at highway speeds,
electrics don't move enough air to help much)
Thirdgen's cooling system was designed back in the
55mph days and the ram airflow is not the best-
On my car with original clutch fan,'84 model aluminum
thin core Lg4 radiator,L83 350 engine,would often
try to heat up when running fast on the highway-
220-230*(no problems at all at lower speeds,even in
hot weather with A/C on) so on one very hot day,110*
(1995)tried a flex-a-lite flex fan i had on hand-cured
the highway heating problem completely! would not
get above 190* there was some high rpm noise and
h.p. loss noticed though-with stock pulley ratio,the
fan turns at about 7800 rpm with engine at 5500 rpm
so put the clutch back on when the weather cooled
some. later in 1995,made an engine oil cooler system
using parts from a 1983 cop impala,mounting the oil
radiator underhood in the charcoal canister area
with specially made 8"electric fan that turns on at
220*(man.overide too) this helped bigtime with the
highway heating problem,dinky lg4 radiator was ok
then with the clutch fan.I got an aftermarket aluminum
radiator i will install later-then cooling system will be
perfected!

Rolling Thunder

Yea you might be supprised electric fans are not all there cracked up to be. They have there advantages no doubt but when it comes to maximum cooling nothing beats a large mechanically driven fan. That is of course with the appropriate cowl to seal it to the radiator.

fryer1979

I'm looking at buying a flex fan that will fit inside the factory shroud, the biggest issue should be getting it spaced towards the radiator just right. O one inch spacer should be just fine. My brother runs a flex fan on his '68 Cutlass with a very similar drivetrain to mine, and his temperature never goes over 180. That's mostly what has gotten me thinking this way for a temporary solution.

Thanks for the replies guys, and by all means, keep the opinions coming.

Apeiron

The clutch is a better solution than the flex fan, as long as the clutch is in good working condition.

Rolling Thunder

Well i actually use one of the flex fans and for me anyways the 2 in spacer without a clutch fit perfect in my fan shrowd. Although if you really want a fan that will cool your motor flex fans makes an "RV fan" thats enormus. That with a clutch i think would be as ideal as it gets. I was thinkin about getting that one because i think it would be just about impossable to overheat with that thing but the average flex fan works fine for me. However without a clutch and my oversized cooling system it will run pretty cold on the highway in the dead of winter.

8t2 z-chev

Clutch fan is my favorite for all-around use,but for max
airflow at highway rpm has to be direct drive off of
waterpump pulley as a fan clutch will only let fan turn
a max of 2000-2500 rpm-just freewheels at speeds
above that,regardless of temperature.
the flex-a-lite fan i used,18 3/8 dia,H/D type with blue
hub spider,used about 5-7 h.p at 5500 engine rpm i
estimate. Clutch fan will use about 1-3 hp clutched in
,nil at high rpm (freewheeling) Electric will use about
1/2 hp due to load on alternator.
For best performance a belt drive fan should be
placed halfway into the shroud opening.

305sbc

iTrader: (3)

If it only gets hot when on the highway then the solution to your problem is to install a functioning airdam.
If this is in a 3rdgen (I assume it is) then make sure the area in front of and above the radiator (where the hood latch is) is sealed off with the factory plastic piece and that there are no large air gaps between the radiator supports to the left and right sides of the radiator. The factory plastic pieces in these areas are what helps the airdam to do its job. If your pieces are missing you should be able to find them in a salvage yard.

fryer1979

I am sorry, I failed to specify that this Camaro is a late 2nd gen (1979) and has open air flow through the grill. Never considered installing an air dam though, but my front end may be too close to the ground for that to be effective. I know you were referring to a third gen, but you got me thinking just the same.

So can flex fans be connected to a clutch? Wouldn't that negate the advantage of having a flex fan since it once again will be free wheeling at highway RPMs?

My heating concern is both cruising and highway driving. Although my "cruising" usually ends up being many short bursts to redline in first gear. It's not so much an overheating issue, just I would like to find a way to get it to run cooler without the expense of swapping to an electric fan. In about 5 years I am going to do a whole rebuild swapping to an LS1, 4L60E and an aluminum/electric cooling system. I'm just looking into a temporary solution.

305sbc

iTrader: (3)

You could use a solid fan to control temps at all engine speeds, but I think your best solution is to use natural air flow at highway speeds for cooling - via an airdam and/or better sealing around the sides of the radiator. Sometimes sealing the space between the top of the radiator and hood does the trick.

Blocking off the radiator bypass on the passenger side of the water pump is also helpful in lowering operating temps a bit.

A flex fan is designed to work in a similar fashion to the clutch fan except without the clutch. It may not do what you are looking for since it doesn't movemore air as it spins faster.

fryer1979

I will give blocking off the areas around the radiator a try. Still might give a flex fan a try, even if it doesn't help much on the highway, the $40 sounds like it will keep me a bit cooler around town in the hot months. Thanks a lot for the info. More opinions are always welcome.

crytical point

I used a Flex fan with a spacer on my 83 camaro and on my 78 monza and I will say that I never had any leaves build up around the wipers ever again. They move so much air it will blow water drops up the window at about 2500rpms with the hood closed.

UnderCover89TBI

iTrader: (25)

you either have restricted airflow to the radiator, a flex flan flattens out at higher rpms basically not moving any air. it will not change anything. i think either you have some restriction in the airflow to and thru the radiator. or your radiator core is plugged up enough to restrict waterlfow at higher speeds.

8t2 z-chev

flex fan does not completely flatten out at high rpm
-just reduces the pitch to reduce power usage and
prevent cavatation,use of a flex fan on my car eliminated
the highway heating problem i was having in very hot
weather(air deflector was in place) to check the airflow
generated by the fan vs the normal ram airflow, i placed
a spare 10" electric fan in front of the radiator and
hooked it to a voltmeter so the power generated by the
motor being spun could be observed and the airflow
rekoned-even at 80 mph the flex fan was moving a lot
more air than the ram airflow was providing-(the
grills on either side of the license plate were blocked
by large driving lights,so pretty much bottom
airflow only)-air has to make 90*turn,go up,then
turn again to go into radiator-not the best design,
later model 3rds have more clearance and aren't
quite as bad. some flex fans use quite a bit of h.p.
-tried a 7 blade G.M. flex (of the type found on some
'72-'82 chevys) and it used quite a bit of power at
high rpm(belts started to squeel at 5200) with the
flex-a-lite could only notice a slight power draw at
5500,made no difference in mpg. also tried a
powerfull electric(HD fiero)but didn't move enough
air to help at highway speeds(1/6 h.p. motor,power
full for an electricjust didn't have the power to
generate the airflow for the situation)

fryer1979

I think I will give the flex fan a try. The radiator is brand new and has no flow issues, so there is no blockage causing the problem. Of course there really isn't any major problem, I would just like to see the car run a little cooler. I will try to remember to update on this post with my results when the car is running again in a few months. Thanks for all the input guys.