I was wondering why everyone also converts to an electric fan. It seems that there isn't a single high horsepower FC running the stock thermoclutch fan, even though I have always heard it outflows 90% of electric fans.

I was thinking about switching back to the stock setup for a few reasons: first the stock fan shround fits the radiator perfectly. Second because I won't have to deal with the extra electical load/hassle caused by the E-fan.

Can anybody clear this up for me?

 

i just converted to e-fan and would NOT go back.

the clutch on the belt-driven fan could fail and not work at all, or could lock up and work all the time- killing your waterpump bearing.

ever tried to race, or get on the freeway with the fan clutch engaged? dude its mega annoying.

ive just bought a fan clutch and its already toast, along with a water pump.

is your efan wired to be on ALL the time? if thats the case, get a universal e-fan controller kit for under 20 bucks at a kragen or autobone.

the efan is waaay better, not to mention cheaper. if the fan goes out, go to the boneyard and get another for 40 bucks.


--mike

EDIT: i use the efan out of a pontiac 6000, theres two inches on either side that the efan shroud doensnt cover, but its very effective and only stays on for a few minutes at a time -- whenever the thermostat opens up and dumps hot coolant into the rad.

 

No, mine is not on all the time. I don't see the stock fans being less reliable considering there are tons of RX-7s around still running the stock fan after all these years.

 

You asked, I told. Do what you want.

 

i have used the stock set up on my koyo for a while with no problems it stays cool on the track even during the summer

 

i just switched to an efan mainly for cosmetic and more area to work. and i have to say i LOVE it. at first i was afraid it wouldnt flow enough air....HA! when i was tring to figure out which wire was for low and which was for high i hooked to the low up first and was like "whoa guess thats the high"... then i hooked up the high.... but i love the way it looks and there isnt any noticeable difference in the charging system. my lights arent dimmer or anything like that.

 

The electric motor could fail and not work at all. Or the relay. Or the switch. Or the fuse...

The is no evidence that a properly installed electric fan is any more or less reliable than a mechanical clutch fan. Of course quite a few around here are not properly installed.

I can honestly saw I've never been annoyed by my fan while getting on the freeway. I'm curious to know why you would be. Besides, if the engine is hot enough that the fan is engaged, then it would be hot enough to turn on an e-fan, drawing a similar amount of power from the engine via the alternator.

No, it's not. Nothing you've said has proven any significant advantage over the stock fan. The fan's job is to keep the engine cool at low speed, and a decent e-fan set up can only do this as well as the stock fan because the stock fan does it perfectly. I've used both types of fans over the years and know they both work well, but one is not necessarily any better than the other. You should remember that many new cars still use a thermoclutch fan, which would not be the case if electric fans were "waaay better".

Of course you might need to replace your overheated engine each time too...

Do you want to elaborate on that? It sounds like you bought an old one, so you can't seriously expect that it might not fail too.

This statement shows you don't understand how cooling systems work. The fan does not switch on because the thermostat opens. The thermostat is always open once the engine's warm, varying coolant flow in response to engine temp. The fan should only switch on when the coolant temp rises a bit above normal operating temps, which is higher than the thermostat's opening temp.

 

Anybody else have any input?

 

e-fans are more of a high performance mod to get more performance out of the engine or to replace a failed thermo fan. most cars to this day still use clutch fans because they are more RELIABLE, e-fans are used where a clutch fan cannot fit the application (transverse engines) drag cars use e-fans or no fans at all because they rob valuable horsepower. an ideal e-fan setup draws minimal current from your alternator while sufficiently cooling.

there is a tradeoff to both setups but the generally it is as i said, e-fans are for high output engines whereas clutch fans are more for stockers.

people who put e-fans on a perfectly fine running/cooling engine are only asking for trouble. there are several belts running the stock clutch fan so if one fails there is backups. the clutch rarely fails and i don't know about the validity of a locked up fan killing a water pump.

 

Whether you use a mechanical fan or an electric one, at the end of the day it takes the same amount of work done by the engine to move enough air for sufficient cooling. Electric fans do not give you cooling for free. People tend to over-estimate the power consumption of clutch fans and under-estimate the power consumption of electric fans, leading to the BS idea that swapping to an e-fan will free up "heaps of power".

While it may be true that owners of cars with "high output engines" tend to use e-fans, there is absolutely no reason why you can't use a mechancial fan instead. Any fan is only used at low speed anyway, and the stock fan practically freewheels when not required, so there is no reason why you have to swap to electric. At idle or cruise a 600hp engine needs no more cooling that a 150hp one, so a fan that keeps stock engine temps under control will still work on "high output engines".

As you correctly stated, the biggest advantage electric fans have is in packaging.

 

IAN on this forum made 408whp with his FC, running the stock fan and shroud

His car never got hot on the dyno, while my e-fan car was heating up like a mother

 

Same power as me.

I am now highly considering swapping to a manual fan/shroud now. Thanks for the input guys.

 

Same car as you, and same turbo too

 

wrong, e-fans do not run constantly but a mechanical fan does. a mechanical fan can actually overcool an engine but a e-fan with a thermo switch will only use enough labor to keep it cool when it needs it. i agree that the stocker is a better setup but as i said there is pros and cons to both.

are we having a pick everyone apart week or what?

i feel like i'm in a Michael Moore film where everything is taken out of context..

 

Which is why I said "the stock fan practically freewheels when not required". The amount of engine power absorbed by a disengaged clutch fan is so small it's barely worth discussing. It'd be silly to suggest it as a genuine disadvantage compared to an e-fan.

Both types will only operate as and when needed to keep temps from rising. A properly functioning thermoclutch does not overcool an engine. When disengaged it cannot pull enough air to lower temps any further. I don't know where you got the idea this happens, since every FC came with a clutch fan and I've never heard anyone blame one for overcooling.

Out of context? WTF?

 

I find that statement funny. I hope you know that a car moving 30mph moves more air over the radiator then any fan can. The car itself, moving on the highway at 60mph can "actually overcool an engine" with no fans at all. Please, learn a little more about cooling systems before commenting. Unless your running without a thermostat (which is just stupid) you'll never have to worry about overcooling an engine unless your running 60mph with the clutch in on a -60 deg night.

Go talk to any ITA/IT7 guy, and look at their car. You'll see that they don't even run fans...they don't need to. Moving at 40-140mph provides plenty of cool air for the radiator.

How do you properly cool your car? Its all about making sure air goes thru the radiator, not around it. Make sure the proper ducting is in place...you know, like the one that came stock around the hood latch.

We had 2 electric fans on our autocross car, wired to run all the time while the car is running. They just couldn't cool the car enough...we where having overheat problems all the time. Granted, these where cheap electric fans....about $50 each...but we where running 2 with proper ducting. Switched back to the stock mechanical and never had that problem again. That engine fan moves LOTS of air. And, you've got all of the engines power available to turn that fan. Personally, I'd rather lose a race by a 1/10th of a second then destroy an engine.

 

A mechanical fan CANNOT overcool an engine if you are running a thermostat! DUHH!! Once the coolant temp drops below the rated temp of the thermostat, it shuts off flow to the radiator. Also driving at 70 mph pushs about 10 times more air than any fan and "overcooling" never happens then!

 

The only reason why I converted mine to an electric fan is due to my clutch being faulty and I was not willing to pay a dealer price on a new one. I purchased a dual electric fan at a junkyard for $20 that included the wiring,relays,and a thermostat. I even wired a LED in the car so I know when its on + a overide switch in case the thermostat is faulty. The fan fit in the stock radiator shroud w/minimum modifications. Works perfect! To tell you the truth I could not tell any difference in horsepower. I would not have converted if my stock fan clutch wasnt faulty. I would have to agree w/ everyone else the stock fan is more than adequate. Just my .02

 

My radiator is not in the stock location or the stock angle. Thus, the stock shroud doesn't touch the radiator. That's why I use an e-fan.

 

NZ's right about everything (as usual, lol). The only reason to do it is to clean up the engine bay and give you more room, either for cosmetic or for running pipes/etc, doesn't much matter. If you have no reason to remove it, then don't.

 

Anyways... Another plus for the electric fan is that if you install an electric water pump at the same time, you can have the fan and water pump on after you turn your engine off (like a turbo-timer setup) so that you can reduce the underhood temperatures faster. (not that it would help much anyways, but just a thought)

suds

 

My experience is the stock fan is the most efficient & most reliable, but replacing the clutch is kind of expensive.

When my S4 fan clutch wore out I converted to a flex-a-lite black magic to save a few bucks.
It looked cool and worked for about 6 months when it's control failed.
I replaced the control and 3 months later the motor siezed up.
I junked the flex-a-lite and put in a used Ford Tarus fan with a generic control and it worked fine.

The mechanical fan pulls way more air, so I suspect it uses a little more power.
When you're sitting in traffic in 95 deg heat and 95 % humidity you need all the cooling you can get.

 

I might have to use a Taurus Efan or something, because my supercharger pulley gets in the way of the second v belt pulley for a dual belt setup. One belt seems to handle my fan and waterpump most of the time when I'm not totally revving, but I'd rather be safe and take that fan load off the system.

But I don't like Efans. They are not any lighter or more effective at cooling than the stock fan, and the power drain of the stock fan on the engine doesn't amount to more than 1 hp at 7k rpm. Fan clutches are reliable in my experience, and it goes without saying that they are simpler and already there on the car.

 

Uh, one advantage no one can really argue with is the fact that most people think the e-fan looks nicer under the engine bay, and gives you alot more room to poke/work around.

I know this is a discussion about performance, just thought i'd say it.

I still run the stocker.

 

As a new owner of a immaculate 90 - 7- GX I'm wondering if changing thermostats would help in running cooler?
Also is the temp guage supposed to consistantly be at the half way mark or slightly higher when raced?