Still to hot????????

[Strawdawg]

We really need a fantasy tech forum for this stuff to move these kinda comments to.

A clutch fan is intended to disengage as the engine speed increases in order to reduce the drag on the engine and that puts an end to the 17 hp theory.  At idle, it may take a couple of hp, at most, to drive the fan.

A good electric fan will weigh more than the mechanical fan.  Good electric motors are not lightweight by any means.

With regard to actual cooling by an electric fan, many are disadvantaged from the start as the cfm rating is often a "software modelled" number and the advertised number will be much higher than the real number when the fan is mounted close to the radiator core.  One can verify this by looking at the amperage being pulled when the fan is in operation.  It will be very low compared to what it takes to run an honestly rated fan.   That amperage, whatever its is-low or high, is not free with regard to hp either.  The harder the alternator has to work, the more hp that is consumed to turn it so there is no free lunch other than in the magazine ads.

If we ignore all the bs hp claims, one of the largest weaknesses of the aftermarket electric fans is usually the shroud design.  Many are not very deep and this limits the effectiveness of the air pull thru the radiator core other than directly in front of the fan blade.  Also, some of them actually restrict air flow thru the core when the car is moving-again due to the "shallow" shroud which acts as a wall behind the core.  The better units have deeper shrouds, and, some have doors that open as the car obtains speed from this pressure-otherwise the restriction makes the core area appear smaller and less surface is exposed to moving air.

[burdar]

I'm still undecided on what I'm going to do on my Dart.  The two systems that I hear work very well are the Mercedes fan and the Ford Contour fan.  The Contour fan seems to be popular with the A-body guys.  I think it pretty much bolts right up, has two fans and a temp controller built into the shroud.  Another thing to consider is that electric fans take a lot of power to run.  You really need the fans on relays.  Then, you need to see if your alternator has enough power to run all your accessories at idle.

[Strawdawg]

I'm still undecided on what I'm going to do on my Dart.  The two systems that I hear work very well are the Mercedes fan and the Ford Contour fan.  The Contour fan seems to be popular with the A-body guys.  I think it pretty much bolts right up, has two fans and a temp controller built into the shroud.  Another thing to consider is that electric fans take a lot of power to run.  You really need the fans on relays.  Then, you need to see if your alternator has enough power to run all your accessories at idle.

Not so long ago, the Chevy SSR fan was mentioned frequently on this forum. 

When the electric fans were first mentioned, the Lincon fan and the Taurus SHO's were among the best performing.  Factory fans were designed to do the job but they are always big amperage "pullers" and it takes a strong alternator to support them.  They must use an individual relay for each fan-I would say 40 amps plus a fuse that is large enuf to handle the start up current draw which is substantial on most.

Most factory fans are built for performance and not for slimness or low current draw so they will do the job on the average street car.  IF there is a reason that you need electric, I would suggest trying to find one that will support the hp level of your combination routinely.  The factory usually spends a lot more time on combinations than we do because they have to produce something that works everywhere under all conditions.

[challengerx]

I like most love hp but as stated what good is hp if you can't drive it, which by the way is why I built it. I think I will try a regular fan which leads me to my next prob, can I use a regular fan with my march serpentine pulleys. Will there be room

[burdar]

Does the March system spin the water pump backwards?  That might be the biggest problem.  You should have room for a fixed fan.  You might not have room for a clutch fan.  You'll have to measure. 

[challengerx]

It was my understanding that it worked like stock but I guess I should check

[72cudamaan]

Does the March system spin the water pump backwards?  That might be the biggest problem.  You should have room for a fixed fan.  You might not have room for a clutch fan.  You'll have to measure.

From what I understand the Milodon hv water pump has eight straight vanes instead of curved vanes. That make it unidirectional.
There may be other pumps like that. I don't know about fit though. I'd be interested as I have a serpentine system and would
like to use a clutch fan also.

[V02Barracuda]

Bought a 318/904 Barracuda in 2006.  It came with a flex fan and a very small radiator.  Ripped everything out and put a 340 stroker/Keisler 5 speed in it along with a 1974 Road Runner radiator that I saved from many years ago.  Put the flex-a-lite 185 electric fan in it and hated it.  Pulled a lot of current and cooled the engine OK but should have cooled it better IMO.

Went to Carlisle, found a 416 fan and a shroud for the Road Runner radiator.  Installed it and never looked back.  Keeps the engine nice and cool on really hot days. 

That's my set up and I love it.  I'll never go electric again.

Side note:  About 3 years ago I found a 1974 Firebird Formula 400 4 speed (picked it up for $3,700.00).  It ran great but it had an electric fan in it.  Took it out and bought a fan and clutch from Autone.  Works excellent.  Keeps the 400 very cool. 

I vote for the clutch fan set up.

[cudabob496]

Below is a dyno discussion where a guy gained 17 hp by ditching the mechanical clutch fan.
I think the electric fan on my Cuda weighs around 4 pounds, and draws 10 amps.
Of course, this could all be fantasy!
Should not compare removing the clutch fan to removal of the alternator or water pump.
Trying to remember when in the last 25 years a car was built, in a car magazine, where they
did not use an electric fan.  Is there any car built today, in the world, where they use a mechanical fan?

http://forums.corvetteforum.com/c3-tech-performance/451456-how-much-horsepower-is-the-stock-fan-clutch-costing-me.html

[72cudamaan]

This is exactly why there should be a fantasy thread. So ONE guy says without proof that he gained 17hp. SO WHAT?
As you can see, the responses are all running towards reliability, not maximum hp. As far as I can tell, you are the only one worried about
every little hp gain. I personally don't care if every car in every magazine runs an electric fan, I still don't want too. As stated, cars
with electric fans from the factory utilize a much heavier fan set up with substantially more electrical drain than what you have.
And for a street car WHO cares about a couple of pounds difference? Quit trying to push your fantasy world car on everybody else.
It's getting kind of tiring hearing you spout all sorts of data about your car over and over again. Hang on a minute and I might
slide off of my soapbox.

[dutch]

so.... how about driver weight      cheap and healthy hp..... 

[Strawdawg]

New cars use electric fans primarily for emissions' purposes.  Computer leaves the fan off until the car is somewhere above 200 degs.  This allows the car to warm up as fast as possible and get into closed loop.   This is required to pass government requirements.  It can also turn the fan off at a given speed which not only minimizes the reduction in air flow across the radiator core and allows better cooling with a smaller core and perhaps, more importantly, reduces the load on the alternator which in turn reduces the horsepower fractionally on the engine which translates into a slight improvement in gas mileage.  No question that computer controlled fans are more precise than a mechanical clutch driven fan.

There is also some benefit in being able to build a car designed by an artist.  There is a lot of flexibility in the ability to mount fans at an angle or in an odd position when design dictates something other than a vertical radiator and fan which is required with an engine driven fan.

With regard to car magazines....geez!  Magazines don't stay in business from the money received in sales.  They stay in business from revenues from advertisers.  It is not a coincidence to find credit given to the component manufactures for the parts used and it is less of a coincidence to find they are using parts donated by their advertisers often accompanied by an ad from the primary advertiser on an adjacent page.  Mechanical fans are not a major item any more and no one is going to make a living selling them.

So called magazine tests never show a bad result.  That would result in lost advertising.

[challengerx]

Hey guys not looking to get one another mad at each other, just looking for suggestion. Yes I understand that some radiators and fans or any other part for that matter work different in different apps . I am pretty sure I will never feel a difference of 15 hp or loose a race because of 15 hp, but I guarantee I will feel it sitting by the side of the road over heated. I think first I will put on the shroud and see how this works since I paid for what I have and if that doesn't work put a mechanical on. One other thing, could I test this by just putting a high powered house fan in front of the car to see if it is truly a flow issue

[Strawdawg]

Burdar, sometimes, Rock Auto has the dimensions of the fans when you look them up which might help you decide in advance if they will fit

[burdar]

I don't think a house fan is enough.  Shops that have chassis dynos use much bigger fans that flow a lot more air.