Here is a basic question I am sure any wrench out there can help me with. Situation 72 Chevelle with a semi-stock 350, edelbrock 750 carb, 19" rigid 7- blade factory fan with semi agressive blades + clutch fan.

Question One:
Will converting to a mechancial seven blade fan provide any benefit and/or operating advantages.

Question Two:
is it advisd to consider auxilary electric fans mounted to radiator?

So many discussions on cooling, what is the economical and effective approach to lower operating temps. Thanks for any input!

Lee

I'm in the middle of "imagineering" my fan / shroud assy. on my '64 now. I'm staying with the clutch setup. Saves on HP, and cools as needed. I've used this setup in 2 other chassis with this motor (383) and have never had an overheat problem. A seven blade direct drive is gonna ROAR something awful (I had a clutch freeze up on me once, and it sounded like a 747 on takeoff under the hood).
As far as electrics go, I've not needed one yet. They do make a clean install, and you can get rid of the engine driven fan if sized and thermostatted properly.
The best thing you can do for cooling is run a shroud. This ensures that all the fans work is being pulled through the radiator.

I too will agree...

I think the clutch is the better mechanical choice

I currently run a 7-blade clutch fan, with a shroud, and I have dual electrics that I can turn on when I think I need them (traffic, etc...

Eventually, I will go with all electric fans, but I need to upgrade the electrical system first...

So:

Answer #1, If the clutch is operating properly, no you should see an advantage, in fact, likely a disadvantage using a non-clutching mechanical fans...

Answer #2, Auxilary fans can't hurt, but why not just go with the primary electrics altogether?

I have found the new Stewart high-flow water pump on mine to be the best thing I have tried...

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"Once you go RAT, you never go back..."
TC #1366
Tony
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ON this note, I have read a couple of articles lately that states not to run electric pushers in front of rad. when running a clutch set-up. Something about cancelling eachother out and not cooling as effectively. Dont remember where I read this but I believe in this months Super Chevy or CC.

Although, having them on a switch like Tony does makes sense to me since the clutch is freewheeling at low speed or when stopped in traffic, thus, using the pushers on a switch to move air through the rad is a good idea.

Gonna use the Mark VIII set-up myself after seeing and feeling the amount of air this thing moves on BB_Mikes ride. A great set-up.

Economically speaking, stewart pump or equivalent, an up to snuff cooling system and a clutch fan would do just fine from street to strip. Fixed fans just rob hp.

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'70 SS 396
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