Agreed there is no need for that, but is easier to do so and cheaper. No I don't think $20 extra for a temp control (electric thermostat) and a relay is that much, but I don't think yanking a an electric fan from a junker is a good option at all either. I a firm believer of doing things right the first time, know what I mean?

Now when you say @ speed the air being pushed through the radiator is far more than the fan can move; that is actually a debatable sentence, define @ what speed.

Now picture this scenario, a 10 mph traffic jam, during a hot, humid, sunny day, with temps above 95, do you think your theory will work here? Do you think the e fan will put more stress to the vehicle than the stock one?

As I said before, the sentence is debatable, and we can probably bs this issue for quite some time

How can you lost power because of the extra load on the alternator? Does that mean that when you add a amplifier to your sound system you are actually losing hp?

Don't think so!

 

Why not? Assuming you get an adequately sized one, why wouldn’t it work just as well on your car as it obviously did on the car it came off? But you think running a fan without a thermostat is OK? Well it has been proven. Why do you think all cars made in the last couple of decades use clutch fans instead of fixed ones, or have thermostatically controlled electrical fans? The speed at which the fan becomes unnecessary will be different for every car. I don’t remember saying it would, but we’re not talking about the stock fan, we’re talking about an electric one. If that fan has a thermostat, it will simply operate for a long and as often as required to keep the car cool. If the fan has to run all the time, it’s too small or something else is wrong with the cooling system. Are you kidding? What do you think drives the alternator? The engine! All electrical loads use engine power. Why do you think the idle speed drops when you turn your lights on? So yes, that amplifier does cost engine power.
My point was at a constant speed the stock fan is still drawing a small amount of engine power (clutch fans don’t entirely disengage), so an electric fan running constantly will have about the same effect. So you’ve lost part of the advantage of having an electric fan.

Bottom line: an electric fan without a thermostat is a waste of time.

 

Amplifier?? Actually, YES!!
It's only a fraction of a HP though.
Ever notice how your revs drop very slightly for a split second when you flip the headlights on? That's because the alternator is being spun in a much stronger magnetic field.. it's harder to turn.
If your amp is powerfulll enough, you will see your revs drop slightly when the bass hits....
I have to STRONGLY dissagree with NZ though.... there is a measurable gain to be had with an electric fan.
The mechanical one, even though it's limited by a viscous clutch, still generates much more parasitic drag on the engine than the electric one.
The electrical power is more effecient than the drive off the engine... (as illogical as that acutally sounds)
It does fee up tons of room under the hood though.
Also- make sure you get one with a shroud, or make one.

I have mine hooked up thermostatically, and to a constant power. It only goes on when I've been sitting in traffic. As soon as I'm moving, it's off in a few seconds.

**IMPORTANT** To those with A/C.... You MUST hook the fan power up to the A/C clutch- so it goes on whenever the air goes on. Otherwise, you will blow all the freon out of the system, and your won't be blowing cold air!

 

How do you blow all the freon out of the system.I can't say I understand that statement.
Oh well maybe that's why I only get warm air this year.But if i'm in traffic and the A/C is on I usually turn my fan on with the switch I have tha bypasses the thermostat.

 

my bro in law that has owned many 7's an fb an fc and owns an fd said its nor good to have an efan for stress on the electric system and doesnt really do n e thing for u except clear space lol but im in florida and im thinkin of the thermo switch from a local parts store and from that what do i do ? ???

 

For startes, how would you know the condition of the E-fan, it might die on you right away, or even worst on a traffic jam, heading to work!

Nope, I have a black magic one that comes with a built in thermostat I won't risk my engine with a who knows how many miles junkyard efan! I you wan't to be cheap then by all means, a thermostat (for the fan) is NOT necessary, unless you live in places where the temp reaches the freezing point.

I was actually talking the about the speed the car needs to be moving in order to surpass the need of a fan (either mech or electrical). In a rotary engine, I assure you is far from the rest of the cars.

*hint*Key word was traffic jam*hint*

As far as I know, you need the alternator wether you have a E fan or not, so you already loose all the power you were to loose with the alternator. With a E-fan, amp, etc you are putting more stress on the alternator itself and not on the engine.

 

Check here http://www.rx7.voodoobox.net
Look under How To. He has a pretty good tutorial type deal for installing an electric fan and includes some pictures and a specific section on wiring.

 

The alternator does not generate the same amperage all the time. Where the hell does the rest of the amperage go if you don't use it? Go study your high-school physics book. Greater amperage draw, greater load on the alternator's coils, greater load on the engine. However, if you do it right, you still don't need to worry about it. Also, if you want to avoid stress on the alternator, buy a higher amperage alternator and swap them. An alternator is an alternator. They all have voltage regulators that maintaine voltage at the same level.

 

E-fan Thread

 

The the cooling system on a rotary is quite conventional, and works exactly the same as every other car out there. The speed at which the fan isn't required has nothing to do with the type of engine; it's determined by the amount of air being forced into the radiator. C'mon, this is high school physics, not rocket science! The alternator takes mechanical power from the engine and converts it to electrical power. Every electrical load takes power from the engine. Fact!

 

I got a fiero fan it is on a switch, the air flow works good by itself as long as you are over 30 mph and under about 75mph. When driving on a highway I must use my elec fan or my temp will rise to 3/4. I like it atleast at 1/2 mark or under. It is attached to my radiator with zip ties and works well.

 

you've got issues. you shouldn't need to use the fan when you're moving past 25 MPH or so.