Notice I said 'Within the limits of your 60s electrical system'

In 1996 when Ford changed the Mustang to an electric fan, it worked very well. But that fan pulls 55 amps. They also started using 130amp 3rd gen alturnators that year. Wonder why?

Those Flexalite fans are helper fans. Yes they pull only about 20 amps but move less than half the air a proper clutch driven 7 blade fan will.

Flex fans are very inefficient and not at all what I recommended.

A clutch fan, when locked up can transmit over 6HP to the fan blades for moving air. (there are bigger ones but this is the Mustang ones I am talking about) A 6HP 12v electric motor would pull over 150amps. Thats why even today with all the upgraded electrics and alturnators, clutch drive mechanical fans are still used on HD trucks. Go look under the hood of an F-250.....

I do heat transfer systems for a living. Take my recomendations or dont. My car runs cool in Houston traffic either way.

I said it was a trade off of HP vs cooling. But if you want an engine to run cool in traffic with the AC on you have to move some air. That takes HP and most of the aftermarket fans come up far short as they were never intended as primary cooling.

The cheapest, and most reliable way of installing a well functioning cooling system for a driver 60s era car is with a proper clutch fan arrangement, proper radiator and a well fitted shroud. I have solved many older car cooling problems simply by removing all the 'fixes' and setting up stock components to work correctly. With the exception of old flex fans. I never install those. Inefficient and dangerous.

 

any fan from a 3.8 liter Taurs or Mustang,Mark VII. The fan will pull about 60 amps on start up and then about 30-35 running so its sorta efficient.It can also be wired for both speeds or only high or low(less amperage)

The mustang went to electric fan not becuase it worked better but for lack of space.The 3g was used for all the electronics on the car(stereo,fuel pumps,power acc.)I have used twin electric fans on a stock alternator as well as full stereo.

 

The answer is within itself. If it takes 5-6 HP to pull the blades on a live or clutch fan, then think of the size of the electric motor needed to move the same amount. 5-6 HP electric motors are kinda large and would be about the size of your starter. I have used single, dual, direct, clutch, and so far the engine driven fans move the most air. Also in a cooling system they are some other things that need to be looked at. The radiator and its capicity, the use of a shroud, the number and pitch of the blades and how close to the radiator they are and the type of coolent. All these will effect how the system works. As far as the HP needed to run a direct drive fan,clutch or not, even 5 to 6 on a 400 HP engine is only like 1.25% and would take the use of a dyno to measure the difference. The use of a clutch fan will futher drop the HP needed when not engauged. Also the pullers are 20 to 30% more effective than the pushers.

 

6hp = 4474 watts (w) and at 12v that is a lot of amps 4474w/12v = 373 amps
The most powerful Flex-A-lite fan draws 18amps and in watts that is 18a * 12v = 216w
And i am not considering (in)efficiecies. So if the stock fan really takes 6hp then there
is no way an electric fan could match it's cooling performace in a car ( unless you ran
a few alternators and batteries with a huge electric motor on the fan and then you would probably loose more than 6hp ) Even if the stock fan only used 1hp that is 746w.......................

I was looking at going electric, but decided on a thermo clutch fan.

Jav