Anyone removed clutch fan and replaced with electric?

[jcp240z]

Does the N62 have two DME outputs? One to control the aux pusher fan like all the E53 and one for the new elec puller fan which replaces the mech one? How are the controlled? Is the output just mirrored and the two fans operate in parallel with the same control logic as the aux fan? I have been looking for some info but can't find it on this.

[upallnight]

Originally Posted by trader4

Has anyone that wants to increase HP by getting rid of the primary engine cooling fan stopped to think about the HP involved? You have a 225HP engine. How many HP do you think it takes to run that fan? A furnace blower motor is only 1/3 - 1/2 HP. That engine fan is more like a fractional HP window fan motor in terms of energy consumption. If you think youi're going to notice some difference from what is probably less than 1/8HP difference, you're kidding yourself. If you think you notice it, it's like someone taking a placebo energy pill and thinking they suddenly are all pepped up. And then you're making up for the airflow with an electric fan? So, the alternator is loading the engine, making electricity, then driving the motor, and this is a good thing compared to a direct drive fan?

You BMW guys are a strange bunch. You buy these cars because of the alleged great Geman engineering. Then you tear it apart and try to re-invent the wheel. Two of the aux electric fans have failed in the X5 here so far. The original mechanical fan, it's still running.....

[m5james]

Originally Posted by trader4

Has anyone that wants to increase HP by getting rid of the primary engine cooling fan stopped to think about the HP involved? You have a 225HP engine. How many HP do you think it takes to run that fan? A furnace blower motor is only 1/3 - 1/2 HP. That engine fan is more like a fractional HP window fan motor in terms of energy consumption. If you think youi're going to notice some difference from what is probably less than 1/8HP difference, you're kidding yourself. If you think you notice it, it's like someone taking a placebo energy pill and thinking they suddenly are all pepped up. And then you're making up for the airflow with an electric fan? So, the alternator is loading the engine, making electricity, then driving the motor, and this is a good thing compared to a direct drive fan?

You BMW guys are a strange bunch. You buy these cars because of the alleged great Geman engineering. Then you tear it apart and try to re-invent the wheel. Two of the aux electric fans have failed in the X5 here so far. The original mechanical fan, it's still running.....

It's not necessarily going to add power, it's going to free it up. You're missing the point and your argument is invalid...BMW themselves ditched the mechanical fan and installed an electric fan on the facelifted X5. Maybe they know something you and I don't? Maybe they caught wind of the FACT there are 5, 7, 8 and X series vehicles out there with DESTROYED hoods, radiator hoses, radiators, etc because the fan clutch survived but the brittle plastic of the blades themselves will fracture from centrifugal force. How about you know the facts before coming in here all patronizing and acting like a know-it-all when you don't.

We're not reinventing the wheel, and BMW doesn't make everything the best of the best. Forums like these are intended for helping those of us who want to improve on where BMW may have dropped the ball, Dinan and other tuners are in business because BMW left HP on the table. BMW made parts in mass production because it was easier to assemble even though it may have been robbing power. Great, your mechanical fan is still running...get onto Google and do some searches of what happens when the fan blades decide they no longer wanna be there, regardless of how good the condition is of your clutch.

You don't wanna improve on your base model 3.0 engine, more power to you, but don't call us a strange bunch because we wanna fix a design flaw that BMW has since changed in the later model years by incorporating themselves what we're trying to do on our own.

[J.Belknap]

The redesign of the mechanical fan ensures blades stay in place if the clutch fails.

[bcredliner]

Originally Posted by trader4

Has anyone that wants to increase HP by getting rid of the primary engine cooling fan stopped to think about the HP involved? You have a 225HP engine. How many HP do you think it takes to run that fan? A furnace blower motor is only 1/3 - 1/2 HP. That engine fan is more like a fractional HP window fan motor in terms of energy consumption. If you think youi're going to notice some difference from what is probably less than 1/8HP difference, you're kidding yourself. If you think you notice it, it's like someone taking a placebo energy pill and thinking they suddenly are all pepped up. And then you're making up for the airflow with an electric fan? So, the alternator is loading the engine, making electricity, then driving the motor, and this is a good thing compared to a direct drive fan?

You BMW guys are a strange bunch. You buy these cars because of the alleged great Geman engineering. Then you tear it apart and try to re-invent the wheel. Two of the aux electric fans have failed in the X5 here so far. The original mechanical fan, it's still running.....

When you read the thread you must have missed the post about HP required to turn both the clutch fan and how much the alternator takes to drive the electric fan. You missed that I don't have a 225HP engine. You missed what CFM electric fan is needed to be equal to or greater than the CFM of mechanical fan. You also missed where I posted that there is a wide range of opinions about what the net gain of available horsepower is and nothing on an X5, and, because of that I spoke to techs at both Spal and Flex-lite. On the other hand, at my age, I could have read and forgotten all that. I only need one movie to watch. It is new every time I watch it.

It is an assumption that all of us bought an X5 because of German engineering. I bought it because of appearance, performance, it sits high enough that I don't feel like and ant on an elephant trail here in pickup truck land and for the room to pack stuff for vacation and trips to Lowe's.

Replacing the clutch fan with an electric fan is not reinventing the wheel. Using your analogy it is putting tires on the wheel instead of riding on stone.

I don't know what X5 you have as it is not in your signature, might want to do that instead of posting disparaging remarks to you strange BMW guys that seek improved handling, performance or enhance the appearance of their X5.

Food for thought-- It's never a good idea to go to the barn dance with your spurs on.

Oh, see I almost forgot, you must have missed the answers to your questions in the thread. I don't want you to have to read it again-- the answers are yes and yes.

[bugbyte]

hey let us know how it turned out after you got it install. A write up would be very appriciated. YFI i went and checked out the new MDX yesterday and you know what I still like my X.

[bcredliner]

Everything is in the garage. I have done the research I think necessary and have thought about how I want to route the wires and where to get the power. So it's install time.

I know the feeling, I keep checking new stuff. I'm never disappointed driving away in my X5. I'm hoping the new X5M will be the ticket. I still won't sell my X5 but it will come out on the weekends. Once it is not my daily driver I will find the route to 800 to 1000 street HP.

Why would I do something so idiotic someone will ask?--just because I can.

[bcredliner]

Originally Posted by trader4

I didn't miss the numbers on how much HP it takes to drive the mechanical fan versus an electric one, because there aren't any numbers. You yourself said:

"I'm done with my research. I was not able to find the CFM of the existing clutch fan. "

So, you don't even know the CFM, yet now you're telling me that the replacement needs to be greater than the original? How about we make it 2X a number you admit you don't even know. You think you can move 2X the air with the same HP that you move 1X? And what size engine you have is irrelevant, because unless you've replaced any engine with some 10HP moonbeam engine, you're not going to see a difference in HP to the wheels that's of any significance or noticeable by removing the fan.

Just from working with various engines and motors over the years, one gets a sense of how many HP it takes to run a fan. Take a look at the rating on a window fan for starters, it's in the ball park. Hint: It's not 5hp, 1hp, not even 1/4hp. Hows that compare to the HP of the engine? So, there's that. And you then still have to power the replacement fan via the alternator, electricity isn't free energy. And there is also the issue that over most of it's working life, the mechanical fan is essentially force fed air by the car moving at speed, further reducing the power it takes to run it.

Which BMW I have is irrelevant. It doesn't change physics. As to the alleged answers to my questions, the questions I posed were:

Have you stopped to think about the HP involved?
How many HP do you think it takes to run that mechanical fan?

So, obviously "yes" can't be an answer to the second one.

I see no indication you are open to considering anything I offer to you. I would suggest there is a chance that could be beneficial. It serves no purpose if I am entrenched in my opinion and contrary based on years of experience and the sense I got from that. My decision is from a collect of facts, logic and common sense rather than the seat of my pants.

There is no necessity to know the exact CFM of the clutch fan. The reason I spoke with experts was to fill that gap. I know what the CFM of electric fans used on V8s requiring more demand that don't have an auxiliary fan and also the CFM of some other BMW fans. The new electric fan puts out CFMs a little over the mid range of appropriate fans for those more demanding V8s. I didn't say the electric fan had to be greater. I said equal to or greater. Based on the research I have done I am confident that is what I have done. With my particular application there are going to be some common sense based decisions rather all exacting facts.

The mention I don't have a 225HP engine was only pointing out that you are inaccurate and if that is part of the basis for your rhetoric you should consider that. I didn't say that the HP of the engine matters but in relation to % of released horsepower to engine HP it could be be more significant by the way.

The 1X/2X and other examples you use are not pertinent as the torque needed to generate electrical energy and mechanical energy are not the same. The comparison of a window fan or AC fan is invalid unless you know the associated CFM. It doesn't matter the 'horsepower' of the electric motor. What matters is the CFM that motor produces with a particular fan blade.

I don't care what BMW you have and I didn't say it mattered. I was suggesting you add the year and model of your X5 to your signature. The reason is it makes it easier to help you when you need it if we know that information up front.

The answer to your second question is there is quite a wide range of how much horsepower it takes to turn a mechanical fan out there.That's because all clutch fans are not created equal. My decision to go to an electrical fan was based on a reasonable minimum. I did a value calculation based on the gain and the cost using a cost per HP gain that is fairly constant with all potential mods. It passed.

I will not be going back to a mechanical fan as there are other benefits of an electrical fan. In addition, I can always add a switch to shut it off when I want to or add an adjustable thermostat that will not turn on the fan unless the engine is overheating.

Gotta go, I am about to fall off the edge of planet.

[Helihover]

This was the same question I asked several post ago and some numbers were givin.

The bench test won't prove anything. If it did our cars would run off a lawn mower engine connected to a large alternator driving a big electric motor

Also his engine is putting out well over 225hp (more like 400+ I think) so the HP gains will be even more less noticeable, but that works out on the other side too with the amp draw.

I don't know.... Would love to see some true numbers that came from a real way of testing. I don't even think a dyno would be able to detect such small changes, but who knows.

[PropellerHead]

I think a lot of folks are looking at this as a HP gain when that is not necessarily the benefit I realized in my E39. Much like a lightweight flywheel- no actual HP is realized- the removal of a parasitic draw allows the engine to work with less effort because the clutch is gone. In my E39 over the past 8 years, this translated to faster trips to the redline. I found that I would actually hit the rev limiter even before the RPM gauge said I should be there.

Not only that, but the engine revs the *other* direction (down) much more readily as well. That may not seem like a nice thing, but consider how much more readily I can rev match with a manual transmission. The engine speed is much easier to manage manually.

Of course, few v8 E53's are going to be manuals, but the engine moving up and down the rev ranges more easily is still a benefit realized by the automatic transmission not waiting as long to shift when necessary.

I probably gained zero HP from the electric fan, but I can get *to* the HP I have much more readily after the install.