Electric fan with the factory shroud
 

There are plenty of threads about using a Fiero, Taurus or Villager fans or aftermarket fans with custom shrouds on over sized aluminum aftermarket radiators. But what if you are running a stock factory or replacement radiator and you just want to remove the factory clutch fan assembly and replace it with a more modern/efficient electric fan setup. The factory shroud is very effective, so what if you were to place the electric fan in about the same location as the factory clutch fan assembly. I did some searching but I did not find where anyone had tried this type of electric fan setup before. Maybe someone has and I just could not find it – either way I thought I would share this project.

I had a 16”electric fan out in the garage, it is an old Mr. Gasket #1988. I believe it is just a re-boxed older design Flex-a-Lite Trimline #116 fan. It is marked made in the USA. It has 10 straight narrow blades and is rated at 2000 CFM with an 11.4 Amp draw. It should be fine for my n/a engine. The current design Flex-a-Lite Trimline #116 fan has the same 11.4 Amp draw but is now rated at 2215 CFM due to its new wider blade design. The quieter 16” Flex-a-Lite S-blade #396 fan is rated at 1980 CFM (it only has 8-blades) with 13.5 Amp draw. If I had needed more air flow, then I could have chosen either the Flex-a-Lite Syclone S-blade 16” fan rated at 2500 CFM with a 17 Amp draw or the Low Boy straight blade #118 (puller) 16”fan that is also rated at 2500 CFM with a higher 18.5 Amp draw.

I had to recess the fan into the factory shroud opening to gain the needed clearance between the electric motor housing and the water pump pulley (yes the studs have been pulled). I cut four slots in the shroud and used the included “L” brackets that came with the fan. I secured the “L” brackets to the fan surround with epoxy and screws and then secured the fan in the factory shroud with HD nylon zip ties. I thought about fabricating some aluminum brackets – we will see if I need them later. I converted the harness connector to a sealed Packard Weather Pack unit. I will be using a Hayden #3651 fan controller. I have already installed the FD 100 Amp alternator so the extra current load from the fan should not be a problem.

i would seal up the area between fan and shroud. With foam or something.

Interesting project and great innovation for stuff you already had around the garage.

The one thing I like about my Taurus fan is that getting the factory shroud out of the engine bay make it easier to work on things.

Not knocking that..But it won't draw as good as having the fan against the Fins of the rad.
You are losing a lot of efficiency on that fan by putting it away from the rad.

Actually, just the opposite.
Spacing the fan off the core increases its efficiency and mitigates the "dead zone" below the fan hub.

I've looked into doing this exact thing before but rejected for two reasons....
About the upper third of the fan is effectively blocked by the shape of the shroud itself and spacing between the fan structure and the waterpump snout is tight.

Does your modified shroud/fan fit?

I think if keeping the factory shroud just keep the factory fan.
Only reason I dont run it is for aesthetics

+1

I watercool my computer and can confirm this is true. If you mount a computer case fan directly to your watercooling radiator there is indeed a dead area. A popular and easy workaround to make your fans more efficient is to take a broken fan of the same size. Cut away the fan and motor so that you are left with only a shroud.

The clutch fan is a parasitic drag on the engine, particularly bad at high RPM. The electric fan will free up 2-3 horsepower. Not a ton, but on an NA where gains are scarce it's worthwhile.

2-3 for the trouble and losing the efficiency of the factory fan is not worth it, especially considering heat is the enemy, and technically what about the additional draw of the higher amp alternator?

I'd say it's worth it alone to retain the stock Tool Tray.

What data do you have to show that the factory fan moves more air than the aftermarket fan?

having another 2-3 hp from a 160 hp car will not allow you to win any race.

keep the stock fan and shroud.

It's best feature, IMO.

I just use a magnetic tool tray, its smaller but nothing ever falls out.

Rotary >Pistons

Horsepower gains/losses are a straw man in this debate, hardly relevant.
If the draw on the alt is greater than the parasitic loss from the stock fan, it must also be granted that the efan drain is intermittent whereas the stock fan's drain is constant.
Six of one, half dozen of the other.

The efan does allow for more precise application of the fan and also eliminates the crude and now quite old stock thermoclutch.

are you serious? I have no data, just the word of people who have installed them.


I have never once recalled someone complaining about the amount of air a factory fan moves but there are plenty of electric fan fails. Of course proper fan selection, shrouding, wiring, and controlling the fan all play a part.

Sure. You made a claim about the factory fan being more "efficient" (I assume you mean it moves more air, or uses less energy to move the same amount of air) so I assumed you had some CFM data for the stock fan. My bad.

now your being a wise guy, lol

do you have real world data for electric fans? What method do you use to collect data of a electric fan? The advertised rating when it when it was new?

I'm not, really, I thought you had some data on the stock fan. Getting CFM data for an e- fan stolen off of some other car would be difficult, but most aftermarket fan manufacturers will give you the current draw and CFM of each model.

John

the current draw and cfm rating of aftermarket auto parts store fans seem questonable considering they do not have any shrouding, while factory fans with their shrouding- like the taurus fans always out perform them.

the shrouding and control of the fan is vital for its sucess, any rotary guy who has ever just bolted on a fan knows this.
I had a "3800 cfm" fan that would always allow the temps to climb and this was with a shroud that the shop selling claimed allowed them to track the car even with an AC condenser in place. Removed that fan and installed a taurus fan and the difference was night and day. No other changes made. Now I think a taurus fan is rated at 4000cfm, that 200 cfm difference sounds like nothing so either the zirgo fan rating was BS or the shroud was that much better

to go through the guessing game, wiring, and control of an aftermarket fan for a horsepower or two just seems useless in my opinion

There is some truth to this. I missed that tool tray, but then I got a radiator panel...

I'm not picking sides in this silly debate, BUT the discussion did cause a little epiphany. In watercooling testing and reviews they go to great lengths to test different components. They will setup test benches to control variables and measure results. All of this for most often sub $150 components in a cooling loop that is sub $500 (not counting the actual computer parts).

Here is an example of testing on different positions for fans (push, pull, shroud, no shroud)....again this is for computer watercooling. Don't click on the link thinking you'll find automotive testing!!
Radiator Fan Orientation and TFC Shroud Testing & Review

You can also find similar tests for different fans at different RPMs, radiators using fans at varying speeds/CFM. It gets precise enough that you need to do your research and make sure that if you are buying a radiator designed for low or med fan speeds that you in fact are using low or med fans so that it your system is working as efficiently as possible.

I'm surprised there isn't more testing of this nature for engine cooling....though costs for test benches for engines is obviously going to be more complex/expensive. Still I'm surprised someone with more time/money hasn't tested exactly what you two are talking about.

Rocking the good old Black Magic Flex a Lite 2800cfm fan for over 15 years. Sure the thermostat on the fan died, so the fan was on at all times (not a big issue for me at the time). Not to long ago, the ecu was set to control the fan, still rocking without issues. Crap works so good, that I dont even use the engine/bottom shroud, and temps stay rock solid (DD, and auto x)

We shall see how it reacts on a track day.

A good E-fan, shroud, and installation is the key

,unless you're racing, where 2-3hp matters.

i did some tuning on a totally stock S5 T2, without AC. i was surprised at how stable the temps were, we could make as many 2-3-4th gear runs on the freeway as we wanted, and water temps would go from 195f to 196f, it was remarkably stable.

air temps move around a little, but they were close to being recovered by the time you were slowed down to hit the gas again. i think we started @40c and it would go up to the mid 40's and then come down to 41-42.

up the power, or take it to a race track, and things would be different, but on the street the stock cooling system works way better than people give it credit for

One can conclude that efans are more (or just as) efficient in the automotive industry, I am basing my thoughts on the amount of modern vehicles that are using the electric ones.

A watercooled PC does not have to contend with airflow directed at/through it, it lives in a mostly static environment.
The auto fan must compromise the efficiency of the blade design to allow for better flow when the fan is inactive (a state the PC fan never encounters)...the better the pull ability, the more of a barrier to outside airflow the fan becomes.
Hence the use of diverter flaps in some shroud designs.