you don't need the replacement pulley. just get a smaller belt.

 

funny you mention this b/c i was looking for one today, and also checked evoms & spp to find nada.

 

ecstuning sells kits, i think. my internet is slow here or else i'd check for you.

 

From what I can tell, ECS's kit (ES#1693) is an OEM style replacement for the existing electrical radiator fan (accessory fan) vs the clutch fan. I would be glad to be proven wrong though.

 

yes, ecs does sell one

http://www.ecstuning.com/stage/edpd...v2.cgi?make=Volkswagen&engine=1.8T&model=Passat B5&submodel=FWD&category=Engine

 

PES tuning used to sell one - I don't remember seeing it after they revamped their website, though.
It was listed under Audi A4 of course...

 

Nay, I looked all around and couldn't find anything associated with an EFK.

 

Maybe www.supremepowerpart.com or www.evoms.com

 

They don't have anything. All the kit is is just a slim line fan and a few screws. You can get a fan from summit and fab some brackets to mount it.

 

i put together my own parts from thefanman.com and ecs.

 

Can you describe in a little more depth. What part did you get from ecs, and what size/kind of fan did you get. I was thinking of doing this to.

 

Yes I did, I corrected myself

 

I have the SPP kit installed.
Do you want me to look at the fan I see if I can find a part number?

 

Yes please.

 

Back in a few...

 

Pardon my ignorance (and my loathing for acronyms) but what is an EFK, and how is it better than just buying a new viscous coupling for the fan?

 

efk = electric fan kit
basically it better because you take out the pulley driven fan and replace it with the electric one so it just frees up some hp since the engine dosent have to power a fan

 

Um...the engine still has to power the fan. Where do you think the electricity is coming from? Furthermore, the belt-driven fan is going to be more efficient, because the power used to spin it doesn't have to be converted from mechanical to electrical and back to mechanical again. Maybe using an EFK lets the engine rev a little faster, but that's about it; the power to keep the fan spinning at a constant speed is going to be exactly the same -- or more -- with an electric fan. Why do you think they spec'd a mechanical fan to start with, if it's more expensive, unless it has some other advantage?

The only way I can see an electric fan saving energy is if it isn't on all the time, like the auxiliary fan. The 1.8t makes too much heat to be left idling without a fan constantly sucking air through the radiator. While this may be an acceptable solution for people who get to drive on the highway a lot, it sounds like a bad idea for people like me who get to commute in bumper-car traffic almost every day.

 

Nay, the viscous fan, much like everything belt driven on the car, is parasitic. Every pulley that you have your accessory belt turn is another added load on the engine and hence less power and less throttle response to the drive train.

Electricity in your car is relatively 'free' power. Meaning that since the accessory belt is already driving the alternator and charging the battery regardless of load, going from a clutch fan to an EK means 1 less pulley leeching power and throttle response from the drive train at no 'added' cost.

Please note the ' ' around certain words in my explaination. I'm, by no means, saying that an EFK can defy the laws of energy, I'm merely saying it reduces (vs adds) to the load of an engine.

 

yes, the engine has to power the fan...through the alternator, which is active regardless of whether or not you have an efk. and there is a minor gain from an efk, since the engine doesn't have to run the pulley for the efk. is it gonna make a huge difference? no. but if you've gotta change it anyway, go with the efk.

 

Sounds like you need a refresher course on the law of conservation of energy.

The alternator gets harder to turn when the current demand increases, because a greater percentage of the total horsepower applied by the serpentine belt is being converted into electrical power; that's why the engine revs dip a little when you operate the power windows, for example. (another good example of this is the gasoline generator behind my parents' house; when the main power is out and they use the generator, it damn near stalls when they first turn on their electric stove.)

The electricity needed to run the electric fan is by no means "free", and assuming the fan moves the same amount of air as the belt-driven fan does, it's not even "cheaper" than the power needed to drive the belt-driven fan. Furthermore, the alternator is NOT always charging the battery; if it were, the battery would explode (or at least boil over). The alternator is designed to control its power-generating capacity according to actual load -- there is no "excess power" being generated, like there used to be back in the bad old days.

I'd like to say that anything you're saying is accurate, but it just isn't. Now, there may be some other component to the belt-driven fan that saps power -- something neither of us has thought to mention in this thread, perhaps -- but it is simply impossible for one device to do the same work as another comparable device without expending the same energy.

 

Wow, big words from someone who doesn't know much about how the factory fan in their car works.

The reason that the EFK makes sense is because the fan does not need to be spinning at all times. A viscous coupled fan is inefficient/ineffective for several reasons. First, a viscous coupled fan will never be able to spin at the same speed as the engine or whatever belt is driving it; there will always be some slipping and this makes it inefficient for the amount of air flow it provides: the slipping is wasted friction heat. Second, the viscous coupled fan will always be spinning and loading the engine, even when it is not needed to provide air flow (ie at highway speeds or lower speeds in cold weather). Third, when the engine speed is low, then the fan speed is low and this is the worst of both worlds when you are sitting in traffic in the middle of the summer. An electric fan overcomes all of these obstacles: it is only used when needed, the electric motor directly drives the fan, and it can provide maximum air flow when it is most needed.

 

I'd imagine the extra belt driven device would add friction.
Plus, the alternator may be more effecent in generating power to spin the same fan.

 

JB, anything from peeking at the fan?

 

It's pretty much pointless to argue that one is definitely more efficient than the other, because we frankly have no measurements to base such a claim on.

The only measurement you need is a "butt dyno comparison" of before/after an EFK install. The difference is noticeable...between 4-5 crank HP more (conservative estimate) after the OE fan deletion and EFK install.

Granted, the VR forces the alternator to supply more "juice" (and greater torque "drain" from the alt. drive belt) when the fan is running.

 

Also, douchexaethera, keep in mind that the B6 and B7 Audi A4 1.8T engines have two OEM electric fans where as the Passat has one electric and one belt-driven fan. It's the same engine. Is Audi wrong?

The EFK also weighs about 1/3 of what the heavy fan/clutch assembly does.

Sorry guys, no luck. I wasn't about to find any info on the fan itself -- No part numbers, brand name, nada.

 

would an electric fan kit for the b5 a4 work for the passat? Like the SPP b5 A4 kit?

 

No, I don't suspect Audi is wrong, but I also doubt the dual electric fan setup in the new A4 has anything to do with better cooling or more horsepower. More likely, it's simply a way to avoid having one more pulley, one more belt, and a viscous clutch, all of which can fail if you beat the hell out of the engine. Not to mention, the electric fans aren't connected to the engine block, so they don't move side-to-side when the engine changes speed, and so they can't possibly bang into anything.

Also, while the A4 still has a longitudinal engine, the new Passat has a transverse engine; you can't put a belt-driven fan on a transverse engine. They may well have opted to put the dual electrics on the new Audis just to eliminate unnecessary non-interchangeable parts between the two versions of the same engine.

I also doubt there's that much power to be gained completely disregarding power loss due to the mechanical-electrical-mechanical conversion; yes, the fan spins fast when the engine is revving high, but at highway speeds I expect the wind coming through the radiator does a good job of helping the belt-driven fan overcome the fluid drag in the clutch.

So yeah, I can think of several reasons why VAG switched to dual electric fans, but more effective cooling and more horsepower are not among them. 5hp is impossible to control for in any kind of test. My car makes 5hp more on a cool morning than it does on a hot afternoon.

 

Bumping this up. Anybody have this on a 1.8T that can snap a few pics and rate the install? Possibly a parts listing? I'm looking to have this fan turn on ~20F* before the aux fan since I have a 1.8T and want to make sure it is cooled properly.

I've been thinking about it a lot since it has gotten warmer. My AMB engined 1.8T A4 is so much more responsive to throttle input than my chipped AWM 1.8T. Always has been. Then I noticed revving thru a parking lot yesterday, when the revs got higher, the engine got really loud. It was the viscous fan doing it's job. Man, that puts a load on the engine.

Audi without a doubt did this to make the engine more responsive. That viscous clutch really mutes throttle response. Another reason why it feels more responsive in the winter, because the clutch lets it spin more freely in cold temps.