C1 -Clutch fan vs standard fan

[Philip P.]

How much better is a clutch fan over a standard four blade fan? I was asked this question and really did not have a good answer.
Phil

[Tom B.]

Re: C1 -Clutch fan vs standard fan

A standard fan spins all the time constantly moving air through the radiator. You can't get any better than that for cooling. If I remember correctly the idea behind a clutch fan is that if not needed the clutch releases allowing the shaft to spin freely inside the hub thus eliminating the drag and loss of horsepower and performance on the engine caused from spinning the fan all the time. It was a performance thing more than a cooling thing.

Tom

[Philip P.]

Re: C1 -Clutch fan vs standard fan

Tom.
I actually never looked at it that way, that sure makes sense to me on the cooling. I knew of the performance side but I guess I was always under the impression the cooling would be better also. Do you know if the 5 blade clutch fan without the clutch is more efficient than the 4 blade? I have seen the clutch eliminator available but wonder if it is worth the effort.
Thanks
Phil

[Brad K.]

Re: C1 -Clutch fan vs standard fan

Try reading John Hinckley's article "Beating the Heat" in the latest "Restorer" magazine. It goes into detail about why a flex bladed fan may not be the right choice.

[Jim L.]

Re: C1 -Clutch fan vs standard fan

I've converted my bride's '59 and my '60 from 4 blade fans to 5 blade clutch fans.

The immediately noticeable difference was a significant reduction in underhood noise. Even if there were no other benefit, the noise reduction alone would be worth the effort and cost to do the conversion.

Jim

[Tom B.]

Re: C1 -Clutch fan vs standard fan

That makes sense. I would think that a 5 blade fan would move more air also. I think I'll go read John's article. He is a wealth of information.

Tom

[Bill M.]

Re: C1 -Clutch fan vs standard fan

From Corvette News Vol 3 No 4: "Corvette's new optional temperature-controlled viscous fan drive increases power, cuts down on fan noise, and saves gasoline."

No mention of improved cooling for the fan.

But the same issue announces the aluminum radiator for "increased cooling reserve" and "the special cam engines run sweet and cool under the severest high-speed operation."

[Philip P.]

Re: C1 -Clutch fan vs standard fan

Does anyone know the specifications for the 4 and 5 bladed fans?
Phil

[Loren S.]

Re: C1 -Clutch fan vs standard fan

I've converted my bride's '59 and my '60 from 4 blade fans to 5 blade clutch fans.

The immediately noticeable difference was a significant reduction in underhood noise. Even if there were no other benefit, the noise reduction alone would be worth the effort and cost to do the conversion.

Jim

Did you also have to change out the fan shroud on the 59 to the 60-62 three piece job?

[Jim L.]

Re: C1 -Clutch fan vs standard fan

Did you also have to change out the fan shroud on the 59 to the 60-62 three piece job?

No. The change was no more involved than unbolting the 4 blade fan (and spacer, if I remember correctly) and bolting on the new fan and thermo clutch.