TheSamba.com :: View topic

Sun Oct 11, 2009 3:27 pm

Hello,

I realized the other day that it is likely one of the reasons we cannot squeeze 40 MPG out of our vehicles is because the engine has to constantly turn a very high CFM squirrel cage fan.

I know that some of us VW owners are the most resourceful people around, so I have to ask this:

Who has run an electric fan to cool their engine? I realize it is a given that a GM or high output alternator would be required, but if you ran such a setup you would never have to worry about overheating for low speed low rpm situations.

I am seriously considering this.

Sun Oct 11, 2009 4:19 pm

It's been tried many time.

Since no one runs it you can safely assume it doesn't work.

Sun Oct 11, 2009 4:28 pm

tundrawolf wrote: Hello,

I realized the other day that it is likely one of the reasons we cannot squeeze 40 MPG out of our vehicles is because the engine has to constantly turn a very high CFM squirrel cage fan

It's an interesting idea to put an alternator/motor setup to run a fan. It's possible that it would help out with cooling at idle on hot days.

BUT...you can't fool energy conservation. The fan probably does take a horsepower or two to run at high engine rpms. By making the fan an electric motor, you're adding two conversion steps, mechanical->electrical (alternator) and then electrical->mechanical (motor). Both of those processes have inefficiencies and so will work against your goal of trying to improve the overall efficiency of the system.

I know there are computer-controlled install-it-yourself fuel-injection kits out there. Have you talked to anyone who's run one of those in an otherwise-relatively-stock VW engine (one not on a dragster)? That might be an interesting comparison point. I'm told that FI in general tends to be more efficient than carburetors. And one that's specifically tuned to an engine would presumably better still.

Sun Oct 11, 2009 6:02 pm

Glenn wrote: It's been tried many time.

Since no one runs it you can safely assume it doesn't work.
I'm sorry Glenn, I have to say this is crummy advice.

If he travels the path from idea to understanding, Tundrawolf will not only arrive at the answer to his "why not?" question, but have acquired along the way skills that will enable him to deal with a whole class of such questions.

Discouraging such investigations are precisely how we get people who can't time an aircooled VW engine any other way except putting the notch on the distributor where the picture in the book shows it.

Max

Sun Oct 11, 2009 6:11 pm

it can totally be done
i was at the fall bug run in mich here recently and there were a good few bug with the same setup you are talking about
modern alternator and an electric fan

i dont see any reason it can't be done
unless of coures your engine does not produce electricity
no electric no electric fan
yes electric yes electric fan

Sun Oct 11, 2009 6:24 pm

Max Welton wrote: Glenn wrote: It's been tried many time.

Since no one runs it you can safely assume it doesn't work.
I'm sorry Glenn, I have to say this is crummy advice.

Max
Over the years it's been attempted man times, all have failed due to the current draw and either under cooling or over cooling due to load.

But hey... knock yourself out.

Personally my engine runs fine with the factory system.

Sun Oct 11, 2009 7:13 pm

Glenn wrote: Max Welton wrote: Glenn wrote: It's been tried many time.

Since no one runs it you can safely assume it doesn't work.
I'm sorry Glenn, I have to say this is crummy advice.

Max
Over the years it's been attempted man times, all have failed due to the current draw and either under cooling or over cooling due to load.

But hey... knock yourself out.
Not me, you ninny. :lol: I already have my thermo merit badge. :wink:

The pursuit of knowledge is never a waste of time. Even when the answer turns out to be "No".

Max

Sun Oct 11, 2009 7:16 pm

Max Welton wrote: The pursuit of knowledge is never a waste of time. Even when the answer turns out to be "No".

Max
True... it takes many NOs until you finally get to a YES.

That's how I met my wife. ;)

Sun Oct 11, 2009 9:36 pm

Quote: where the picture in the book shows it.

You can't believe everything you read in a book. :lol:

Mon Oct 12, 2009 1:24 am

jared8783 wrote: it can totally be done
i was at the fall bug run in mich here recently and there were a good few bug with the same setup you are talking about
modern alternator and an electric fan

i dont see any reason it can't be done
unless of coures your engine does not produce electricity
no electric no electric fan
yes electric yes electric fan

As was I, and I think you left out the part about those cars only driving a 1/4 mile at a time.

Mon Oct 12, 2009 1:32 am

There's a drag bug in my neck 'o the woods that's got electric fans, just to cool it off after a run though.

Mon Oct 12, 2009 10:39 am

runamoc wrote: Quote: where the picture in the book shows it.

You can't believe everything you read in a book. :lol:
Not to mention Al Gore's internet. :wink:

Max

Tue Oct 13, 2009 11:08 pm

well i aint no expert but like i said it can be done

but like glenn said my car runs just fine without it

its not nessecaty

vw are simple

let us not make them more complicated

Tue Oct 13, 2009 11:20 pm

It would seem like the stock fan is in a perfect location to push the air over the cylinders and that a fan other than the one VW designed would require extensive fan shroud modification to put the air where you need it-I am not very knowledgable about this subject but does anyone make a lightweight fan blade that fits the stock alternator, generator.

Wed Nov 04, 2009 8:28 pm

Well you guys can live with your 1930's technology I am going to push the envelope with a spice of modern technology and make my own custom ELECTRIC cooling and I am doing away with the big ugly dog house.

I can update my engine with EFI, coil pack ignition, a turbo, and dry sump oiling why can't I update the 70 year old cooling design?

Wed Nov 04, 2009 8:30 pm

jesus_chrysler wrote: Well you guys can live with your 1930's technology I am going to push the envelope with a spice of modern technology and make my own custom ELECTRIC cooling and I am doing away with the big ugly dog house.

I can update my engine with EFI, coil pack ignition, a turbo, and dry sump oiling why can't I update the 70 year old cooling design?
Let us know how it turns out.

Wed Nov 04, 2009 9:07 pm

jesus_chrysler wrote: Well you guys can live with your 1930's technology I am going to push the envelope with a spice of modern technology and make my own custom ELECTRIC cooling and I am doing away with the big ugly dog house.

I can update my engine with EFI, coil pack ignition, a turbo, and dry sump oiling why can't I update the 70 year old cooling design?

Why don't you just convert it to water cooling and do away with that "1930's technology" altogether?

Wed Nov 04, 2009 9:36 pm

I'm curious to know how this works out, too. PLEASE keep us posted.

Wed Nov 04, 2009 10:19 pm

GatorJZ wrote: jesus_chrysler wrote: Well you guys can live with your 1930's technology I am going to push the envelope with a spice of modern technology and make my own custom ELECTRIC cooling and I am doing away with the big ugly dog house.

I can update my engine with EFI, coil pack ignition, a turbo, and dry sump oiling why can't I update the 70 year old cooling design?

Why don't you just convert it to water cooling and do away with that "1930's technology" altogether?

Kinda what im planning actually.

Wed Nov 04, 2009 10:21 pm

GatorJZ wrote: jesus_chrysler wrote: Well you guys can live with your 1930's technology I am going to push the envelope with a spice of modern technology and make my own custom ELECTRIC cooling and I am doing away with the big ugly dog house.

I can update my engine with EFI, coil pack ignition, a turbo, and dry sump oiling why can't I update the 70 year old cooling design?

Why don't you just convert it to water cooling and do away with that "1930's technology" altogether?
i drive a bug because i enjoy the simplicity of them if you want something complicated and more modern how about one of these