Pulleys

[TheRoadVirus]

Disregard.

 

[Skandocious]

people talk about the quicker startups, but i don't get y

mine takes forever to warm up and yes, the fan is blowing on it the whole time. but...even with an efan wouldn't it warm up at the same speed? the thermostat won't open until the engine is warm, so y does it matter either way.

it'd make sense if the thermostat was open during warm-up and the fan wasn't blowing. am i missing something?

Good point, I've not actually seen my engine warm up faster since I normally start driving before it gets to full operating temp. I guess I should have said "I've HEARD" it warms up faster. I'll edit that

 

[Skandocious]

Ok... an electric fan isn't spinning until you turn it on or if it's wired to turn on at a certain temperature. Therfore the fan isn't cooling the coolant.. that isn't warmed up. If it's a clutch fan it's always spinning and cooling on startup when it's not required.

Yeah but his point is that there is no coolant flowing from radiator to water pump during warm up since the thermostat isn't open, and so the fan pulling air through the fins on the radiator wouldn't cause change in engine temp anyways.

 

[TheRoadVirus]

Ah, ok. I see what he meant now.

 

[flareside_thunder]

Hell No!I'm gettin back on the UDP talk......None of you have seen a set with your own eyes before or else you would have realized this...when you get the kit...the crank pulley is the only one that is smaller in the ENTIRE setup...the waterpump and altenator pulleys are BIGGER....I'm sure it's physics and Chris can explain it...but geezus......the alt and WP are spinning at the same rate...the crank is what's spinning faster...There IS to gain with them if you don't believe me..lemme pull all the other mods I've done on my truck since then and let you drive the damned thing.....with a 302 especially the smaller crank pulley allows your engine to get up into the higher RPMS helping you get up to speed faster...it is a geat bolt on and well worth the damn money....you get better power and save gas because your engine has less work to do to get you up to speed...Like I said...if you STILL want to argue with me...I kept all the factory damn stuff and I'd be more than happy to prove you wrong...As for the E-fan...i haven't done it personally so I can't vouch...but the same principle applies...less drag on the engine and you might or might now get more HP but your engine will get up to speed faster thus giving you more MPG......They make e-fan setups that OUTFLOW factory fans....the term if it ain't broke don't fix it comes to mind don't it?The reason i do mods is to make something good even better AT COST....rather than dish out another 8 grand for the stuff I've done myself......JMFE

JR

 

[Mr. Stroker]

What underdrive kit did you use?

 

[eco]

Not only are they no value, they can cause major problems if they stop working, which is possible due to their reliability. And they have far less
cooling capacity than a mechanical fan!

They will, however, lighten your wallet!!

I don't know if you are lying, don't know what you are talking about or both, but either way, there are plenty of advantages to the e-fan.

Some advantages in no particular order:

1) The clutch fan being fastened to the water pump pulley means that there needs to be a significant amount of belt contact on that pulley in order to avoid belt slip. For me, this was a big deal because I removed the power steering system in favor of manual steering and removing the PS pump and using a shorter belt cost me a large amount of belt contact on the water pump pulley due to the way the serpentine belt is routed. With the mechanical fan there was alot of slip on the water pump pulley due to the weight/load that the fan puts on the pulley. Getting rid of the mechanical fan allowed me to use the shorter belt without slippage (is that a word?) on the water pump pulley. The e-fan conversion saved me from having to fab an idler pulley to put in the place of the PS pump. Also, might I add, this goes to show how much load there is on that pulley with the fan fastened to it even if the clutch is not engaged.

2) Under hood clutter is drastically cut down, thus making the rig easier to work on. For someone that does their own work, this is a big plus. Also, people like frederic that like to put big blocks in small rigs are able to do so with the aid of the e-fan. Space does not allow with the mechanical fan.

3) Throttle response is improved as is fuel economy. Sure, some folks say "well, the amount of current drawn and the amount of parasitic load at the alt....." but how often does the fan even need to be turned on? For some people, myself included, almost never, so that is a moot point. On the rare occasion that the fan gets turned on it isn't even on for very long. If the fan were on ALL THE TIME then that would be a different story.

As far as cooling capacity, that depends on the fan in question - they are not all equal. Reliability? Well, that also depends on the fan in question. I have one in a Pontiac car that has been in there since 1990 - no problems. Sure there are more failure points, but a clutch is also a failure point that is not known to last forever either. Also, if high quality parts are used in an efan conversion and it is well designed and engineered, reliability will not be an issue. If Joe Hack does it, then thats a different story.

 

[flareside_thunder]

I actually bought my kit used from a buddy of mine...(same guy I get all my go fast goodies from) and it is a March underDrive Pulley Set......

JR

 

[Bob Ayers]

Bob I'm not sure I've ever disagreed with anything you've said but I've got to step in and call you out here...

I did the Taurus fan swap on my truck and I'll never look back. The improvement in throttle response over the clutch fan is incredible. No it didn't go and add 40 horsepower but, like I said, there was a noticeable improvement in throttle response and a very small improvement in gas mileage. And rightfully so. The clutch fan adds an incredible amount of weight, and thus load, onto the water pump pulley, and thus adds parasitic draw. And yes the fan is often times disengaged but due to friction in the clutch mechanism it is always going to be spinning SOME, not to mention there is the weight of the clutch mechanism and the arm creating a leaver on the pulley.

I'm not expert but it seems to me that completely removing that fan would offer benefits. I haven't needed to turn on my efan for MONTHS... That's a lot of power/gas that I was wasting spinning that big heavy fan for no reason before. Not to mention that I've also heard the engine warms up faster without the fan spinning.

As for not having a cooling capacity? That depends ENTIRELY on the type of engine, radiator, and fan being used. I know that if I let my truck idle for too long at a stop light and my temp gauge starts to ramp up, I can flip the switch on to LOW speed and watch my gauge drop to normal operating temp in a matter of 20-30 seconds.

Reliability? Okay you got me there... I guess an electrical fan motor would be more prone to going out than a clutch fan... But I do know many guys that have had to replace their clutch fans so this one could be a tossup...

Yeah I don't have facts and numbers to back these things but, but I've done the mod to my truck and I'm willing to put MY reputation on the line and SO BOLDLY declare: the efan conversion is worth EVERY PENNY.

Just my .02

First off, "BUTT DYNOS" are not accurate at all!! All you and Eco have given about e-fans is nothing but lip music! Lets see some real data (dyno run charts, etc. ) from somebody that's truly independent (not an e-fan manufacturer)!

I think both of you are forgetting the load the alternator puts on the engine with the e-fan drawing current.

Eco, the e-fan setup is MUCH less reliable than the mechanical fan/clutch! Not only do you have the electric motor, you have the temp sensor, controller (which contains a relay), wiring, and connectors that can fail! You mention the clutch, but did you ever consider how they fail? The bearing normally seizes, causing the fan to run all the time. This type of failure will not cause an over heat condition like an e-fan failure will!

......Oh, and check it out.......look for a diesel with only an e-fan!! Even the Chevy Silverado uses a mechanical fan with a towing package on the 1500, and 2500 on up!!


I'm done, this is a free country, and if you want to waste your money on these types of useless, and inferior mods, go for it!!!

 

[Bob Ayers]

2) Under hood clutter is drastically cut down, thus making the rig easier to work on. For someone that does their own work, this is a big plus. Also, people like frederic that like to put big blocks in small rigs are able to do so with the aid of the e-fan. Space does not allow with the mechanical fan.

Say what?? You don't realize that the pulley is still on the water pump, and the drive belt(s) are still in place? Try measuring the mechanical fan, and the e-fan! The blades are thinner on the e-fan, but this has something to say about cooling capacity, when you consider the MAX RPM of an e-fan is around 2K RPMs, and much less blade surface area!

 

[Bob Ayers]

I actually bought my kit used from a buddy of mine...(same guy I get all my go fast goodies from) and it is a March underDrive Pulley Set......

JR

E-fan, and UDP! Brilliant combination! You put a high current load on the alternator, and you limit it's output by slowing it down!!

 

[TheRoadVirus]

Lmao, did you even read his post? He doesn't even have an electric fan. And he also mentioned that in his UDP set his crank pulley was the only smaller pulley. He said the alternator and water pump spin at the exact same rate.

So where are you pulling all your information from? If you've never had an electric fan how do you even know what you're talking about? Oh, I guess you must have gone and done a dyno with and without since that's what you're getting all worked up about.

Show us your source, smartguy.

I don't understand how you can flatout refuse to reason, you're wrong! If you can't figure out why an electric fan puts less parasitic drag on the engine and therefore allows it to spin more freely compared to the clutch driven fan, you've got a problem. It's not a difficult concept to comprehend.

 

[Bob Ayers]

Lmao, did you even read his post? He doesn't even have an electric fan. And he also mentioned that in his UDP set his crank pulley was the only smaller pulley. He said the alternator and water pump spin at the exact same rate.

So where are you pulling all your information from? If you've never had an electric fan how do you even know what you're talking about? Oh, I guess you must have gone and done a dyno with and without since that's what you're getting all worked up about.

Show us your source, smartguy.

I don't understand how you can flatout refuse to reason, you're wrong! If you can't figure out why an electric fan puts less parasitic drag on the engine and therefore allows it to spin more freely compared to the clutch driven fan, you've got a problem. It's not a difficult concept to comprehend.

Long read, but hopefully you can comprehend this!!

http://bbs.zuwharrie.com/content?topic=12721.0;wap2


And you obviously missed this, previously posted:

http://www.aaroncake.net/rx-7/efanmyth.htm

 

[TheRoadVirus]

I already saw that RX7 link, I just didn't bother posting about it since it's all heresay. Isn't that what's been bothering you? The buttdyno? I don't see any dyno graphs in either of those links.

And I guess you didn't fully read what you just posted, Bob. That article actually proves the point we've all been arguing with you. Read the bottom. Oh and unless you haven't figured it out yet, with an electric fan you have the choice to have it running or not. And from what I've gathered most people don't have it running very much. Unless they're stuck in traffic and so on.

You haven't fazed me, I'll be still be ordering myself an electric fan and some underdrive pulleys.

 

[Bob Ayers]

I already saw that RX7 link, I just didn't bother posting about it since it's all heresay. Isn't that what's been bothering you? The buttdyno? I don't see any dyno graphs in either of those links.

And I guess you didn't fully read what you just posted, Bob. That article actually proves the point we've all been arguing with you. Read the bottom. Oh and unless you haven't figured it out yet, with an electric fan you have the choice to have it running or not. And from what I've gathered most people don't have it running very much. Unless they're stuck in traffic and so on.

You haven't fazed me, I'll be still be ordering myself an electric fan and some underdrive pulleys.

Just what I was worried about, your reading comprehension skills!

Here is the information you missed, hopefully you can understand it the 2nd (or maybe the 1st) time you read it:


Cooling Capacity:

By far, the most common misconception is that the electric fan cools better then the stock. People see the high CFM numbers in the catalogues (for example, the Black Magic is advertised as pulling 2,800 CFM, and the Perma Cool "finger chopper" is advertised at 2,950 CFM) and are impressed. The truth is that no one actually knows the CFM rating of the stock fan. It has simply never been measured by anyone in the aftermarket and listed. All we do know is that it is rated at "a lot", more times than not it will exceed 4000 CFM. And to be honest, who cares how much air the stock fan moves? It is more then adaquate as long as it's clutch and the rest of the cooling system is in good shape. The steeply raked blades of the stock fan move quite a lot of air, even if it turns slower then an aftermarket electric unit. Experience has shown that when in good shape, the stock fan is even easily capable of handling a 400HP engine. How much power do you make?


Efficiency:

Of course, you're not necessarily after better cooling. You've seen those TV commercials or catalogue ads that promise "Up to 17 free HP!" by converting to an electric fan. Well, that's simply not true. There will be a horsepower gain for sure, on the order of 0.5 - 5HP, with 17 H.P. reserved for big V-8s using 40 lb fans at 6000 rpms. But remember that the electric power to run the fan must come from somewhere, and that somewhere is the alternator. Electric fans draw quite a lot of current. Most pull surges of 35A or more to start up, then run at 8A-10A. This puts extra load on the alternator. Ever pedaled a bicycle with a generator powered light? If so, then you will know that as the electrical load on a generator/alternator increases, the generator/alternator becomes harder to turn. Suddenly, all that "free" HP you just freed up is once again being used. This time, though, it is being used to turn the alternator. There is also an inefficiency in the whole system. We are converting mechanical energy, to electrical energy, to mechanical again to run the fan. This very inefficient, much less then just driving the fan directly via the mechanical energy of the rotating shaft


Reliability:

Lastly, there is the question of reliability. The stock clutch fan can have two failure modes: the clutch will fail, or the fan will physically break. The electric fan introduces many more failure points: fuse, all wiring connections, physical failure of the fan, failure of the motor, failure of the thermostat


Summary (at bottom, which I supposedly missed):

There you have it. For the most part, electric fans are not recommended as an upgrade unless you have a very specific reason to do so. They provide inferior cooling to the stock fan, and may create other problems if improperly installed. If you want to install an electric fan, I have done a basic writeup of the generic process.

with an electric fan you have the choice to have it running or not.

Thinking that this is an advantage shows your technical ability! Let me tell you what happens when you forget that your e-fan is off...........it's possible to burn up your engine!!!




That's it......if you don't understand it by now, your hopeless!!!

 

[Skandocious]

I think both of you are forgetting the load the alternator puts on the engine with the e-fan drawing current.

Okay, but the point is that the fan almost NEVER runs.

 

[Skandocious]

Let me tell you what happens when you forget that your e-fan is off...........it's possible to burn up your engine!!!

If you're having problems like this with your efan then you're incompetent and should NOT have installed it in the first place.

 

[Bob Ayers]

Okay, but the point is that the fan almost NEVER runs.

If the e-fan is wired correctly, it should run whenever the AC compressor runs........And the clutch on the mechanical fan is normally not engauged!

 

[Mr. Stroker]

Ok i talked to my buddy who i help in his performance shop. He said E fan it. In the winter time he doesnt even turn his fan on! Only time he uses it in the summer is if its very warm out, hes at the strip, or sitting in traffic. The E fan is in a truck thats got 450 RWHP, he ordered a 392 Crate engine thats going to put out 500 RWHP, yea do the math at the hp at the crank, he said he will be running that very same fan. Truck runs 10's in the quarter with N2O. I think im gonna do it, i want to get rid of that ugly shrowd.

 

[Bob Ayers]

If you're having problems like this with your efan then you're incompetent and should NOT have installed it in the first place.

"Incompetency and installing an e-fan"


Is there a connection here???