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Electric Fan, AGAIN
Posted by: vairmech ()
Date: December 14, 2017 07:22AM

The question has been asked and answered many times before like way back in 2007!
In the below post is what I wrote about after the tests were done and I will also include the graphs from the data logger. Yes we used a data logger!
There have been many theories put out on how to cool the Vair engine including hydraulic. Until there is a built and proven part(s) NOTHING aftermarket works. Again I know people say they drive these on the road but show me the data log graphs. Also the below was being marketed as you could install it on ANY street car and drive anywhere.

Here is the written report from Bob Helt, Frank Parker and I; (I warn you it is long)

COOLING THE CORVAIR ENGINE
WITH AN ELECTRIC FAN


With the knowledge that the stock Corvair cooling fan consumes some 14
horsepower at 4800 RPM, and even greater power at potential racing speeds,
enthusiasts have long sought a remedy for this considerable reduction in engine
output. If somehow, the stock engine-driven cooling fan could be replaced by an
electric-driven fan similar to those now being used on current production cars,
then the horsepower required for cooling could be reduced. There have
previously been many attempts to accomplish this feat, but none has ever been
entirely successful, although rumors abound with success stories. Despite this,
the concept remains alive with the hope, that maybe there might be some way to
accomplish this cooling feat; something previously overlooked or some new
piece of equipment that might do the job. If this cooling method worked, not
only would considerable engine power be saved, but also any potential fan belt
problems might be side-stepped too. One of the initial problems when trying to
compare the stock cooling setup to an electric fan is the confusion of CFM
ratings. The stock fan is rated somewhere around 1400 CFM at an engine speed
of 4000 RPM, while many electric fans are rated at a much higher CFM. This
leads one into thinking that the electric fan might flow more air. It isn’t so,
but it’s easy to get confused. The problem is that the electric fans just don’
t develop the kind of air pressures required to force the air over the
engine restrictions.
At the 2005 International Corvair Convention in Portland, Oregon,
a company, Vairhouse, of Reno, Nevada was displaying an electric
cooling-fan setup they were manufacturing and selling. They not only had the unit on
display, but they also had a Corvair equipped with their cooling unit that was
being driven around the convention area. Complete engine cooling was being
claimed and the rumor was that the Corvair car had been driven from Reno with
this unit doing the total cooling. If true, it would represent a major
milestone accomplishment.
With this new electric cooling-fan system now for sale and
available, we decided to purchase one and run some of our own, relatively
impartial, tests to see how good this unit might work. As far as we know, this would
be the very first actual independent testing of any similar cooling setup. All
previously tests were, of course, run by the system designer/builder and
actual facts or reports were seldom released.
So it was, that we obtained this new cooling system, designed to
completely replace the stock engine- driven cooling fan on a Corvair. Ken
Hand generously offered to install the system on one of his Corvairs and run the
tests. Frank Parker, a Chevrolet engineer (of Corvair/Northstar fame)
instrumented the test Corvair for data collection and assisted Ken in running the
tests and evaluating the data.

Bob Helt


The Tests
First off I must apologize to the group for taking so long to finish this
electric fan test. I have had some personal problems in my life along with
trying to run a convention. BUT, the electric fan test has finally been
accomplished! Among other things, I lost the use of the car that we started the test with and the owner wanted nothing to do with any of the testing. We did get base line testing done on the first car so we have 2 cars with base line
tests. I think the comparison of the results will surprise you when you look at
the stats.

I also have to thank Bob Helt for supplying the fan kit. Without his
offering this test would never have happened.

Now, what I am going to talk a little about are the basic tests, but
mostly about the kit in general and what it takes to install the kit. The base
line tests were very interesting. On the first car we were able to get a
couple of different outside temperatures and again the numbers will be
surprising to look at, but as I recall the engine temps change with the outside temp, not directly but on a bit of a curve. With the second car base test we had a fairly warm couple of days but the electric fan test day was decidedly cooler than the base line test. We measured outside air temp, oil temp, head temp and the lower heater plenum air temp, MAP and RPM. The oil temp was taken at the oil pressure switch sender hole; the MAP was taken from the balance tube; the head temp was taken from a probe that was bolted against the head boss
where the overheat switch would mount, and held there with a washer and a bolt;
and the air plenum temp was taken in the heater shroud and shielded from the
exhaust manifold radiant heat by the shield that is there for the thermostat.

I need to describe the cars that we did the tests with. The first base
line tests were done on a 1965 Monza with a 110 PG. The second car was a
1965 Monza with a 95 PG. Both cars were what anyone would drive most anywhere.
Specifically, the second car - the 95 PG - was a borrowed car and as I drove
it I was mildly surprised at how well it ran. I hadn’t ever worked on this
car either!

To start the electric fan install, of course, I had to take apart the top of
the engine, all the way to removing the top cover. I then trial fitted
everything. I have to say by the initial look of things I thought I would have
this on in a couple of hours. Well, after really getting into it I found out
that the kit is not really a complete ready to install kit! I had to fabricate a
crank case breather; all the tolerances were very close but did not allow
for the differences in the tolerances of manufacturing. I had to ream, enlarge
or elongate almost every hole to make things fit the way they should. The
exception was the top cover; it fit with no problems at all. In what looked like a really good piece - the alternator mount - I really had to bend a little
to get the alternator to fit in the slot and then I had to elongate the
alternator mount holes considerably. The special bolts needed were supplied with the kit. The one thing that was never really talked about was what to do with the dipstick. The electric fan is larger than the stock fan and I had to
seriously bend the tube in two directions to gain the width needed to clear the
electric fan. Then I had to drill a hole in the fan housing to match where the
dipstick tube was. I also had to match drill where the vent tube would come
through the fan and also figure out how to hook it into the PCV system. Since
this was a very stock engine to begin with, I had to contend with a fuel pump
when installing the idler pulley. There was no mention of how long a belt to
even start with so I had to use the old belt and mark it, and then measure
it to come up with something close. I got three different belts just to be
sure. The first belt was way too short and I couldn’t even get it on because the idler hit the fuel pump. The other belt was way too long and it hit the
distributor before the belt got tight. Thank goodness I got the third belt in the middle as it was just the right size. I did have to pull the idler off the
mounting bolt to get the belt on, but when adjusted properly it cleared
everything, the fuel pump and the distributor. That is a very narrow margin to deal with. There was also a 12 plate cooler on the engine and I had to trim a
notch in the top flange of that to clear the belt. I have to say this is not for the average person to try and tackle. It took me 2 long days to get the
testing and the fabrication done on the second car. Again, the instructions that were sent with the “kit” were very basic and generic. Frank and I decided to hook the fan up with just a snap switch in the engine compartment instead of
any fancy relays or temp switches. We did make sure that the fan went in the
correct direction! As we began the test, what we did was start the engine and
then immediately start the electric fan.

Now for some observations; there was a lot of air reversion through
the electric fan when it was running statically. In comparison the stock fan
had NO air reversion through the fan. Even with the electric fan and the air
doors open, there was still air reversion back through the fan. Not as much
mind you, but there was still air reversion.

On the initial tests we did about 45 MPH on the secondary roads for
about 3 miles and then we did freeway for about 20 miles starting out at 65
MPH; then we hit some traffic and had to slow down a little but then were able
to speed back up to 65 MPH and at the end just before we got off the freeway
we sped up to 70 for about 2-3 miles. The numbers we got were very close to
the 110 PG with about the same curve on temps. You will find the two engines
very similar even though they were a 110 and a 95. I won’t cite numbers because
that will be in the graph from Frank. One of the common misconceptions is
that the 110 is the worst of the two engines for heat because of the
compression ratio. Well, I think we can put that theory to bed.

With the electric fan finally installed we went out for our initial
test and did the same thing as the previous test. It was about 45 on the
secondary roads and once we got to the freeway we accelerated to the 65 MPH speed we did before. Let me back up a little and talk about the head temp only as a reference. If I recall correctly, with the stock fan the temp came up on a
very linear scale and then stabilized and stayed at a decent number. When we
got the electric fan installed and did the same tests the head temp came up
very quickly and not linear at all. It was almost a vertical scale until the air
doors opened and then the temp started to go a little more linear but the
head temp never stopped climbing. We had to stop on the side of the road when
the over heat light came on. We stopped and kept the engine at an idle and the
temp came down very quickly. We started out again and then got into traffic
in a construction zone and the temp was a bit high but stayed low enough to
drive the car. When the traffic cleared a little we accelerated to a moderate
speed and the engine temp kept going higher. We did not complete the same
mileage with the electric fan because the engine would not stay cool at freeway
speeds. We got off the freeway early and took all secondary roads back to
Frank’s house. We found that we could maintain 40 MPH and the temps would
stabilize so we didn’t have to stop and let the engine cool down. Once when we had clear road ahead we accelerated to 60 MPH and the engine soon overheated
again so we stopped for a few minutes to let it cool then started back at our
slow pace. We could hold 45 MPH for quite some time but the head temp would
still start to climb. When I backed it down to 40 MPH the temp would very slowly go back down to the 40 MPH temps which were right at the high end of the
spectrum. So we slowly made it back to Frank’s house and proceeded to remove the electric fan kit and put all of the stock parts back on.


I think when you see the numbers you will know that this electric
fan does not work on a stock engine. As I said earlier, I didn’t do anything
special to the engine, it was an off the street engine that the average person
would try to do this with. I have to also add that “IF” you started out to
build an engine and totally deflashed everything and made sure all the
passages were open to the max in the head and everything was spotless with the lower
shrouds off, maybe, just maybe, the electric fan would cool sufficiently to
drive on the freeway at a decent speed. That test may happen but not in the
very near future as I would have to build an engine just to test the theory
out.

To theorize I would think that the engine would have to be very clean,
all the air passages opened up in the heads, no lower shrouds at all, and
maybe even ceramic coat the exhaust stacks and the exhaust manifold as a
minimum. Then the fan that was supplied may barely keep up.

Frank Parker will have graphs available and I think I will post them
on my web site so Frank will not have to resend the same info time and again.


Ken Hand,

Frank Parker

&

Bob Helt

We will start off with the base line specs of 2 different cars with the stock fan. 95hp stock test numbers. Sorry, the 110 graph was not uploaded and I do not have it saved anywhere. Also the formatting will not stay.

With this chart you can see the temps all remained pretty stable with normal driving.

TIME CYL HEAD TEMP OIL TEMP MAP DUCT SPEED REMARKS
0 90 89 15.3 98 0 idle
1 125 89 15 129 0 idle
2 162 90 16.6 164 45
3 190 97 18 192 0 stop
4 211 106 17.4 213 50
5 226 132 15.1 230 50
6 238 148 15.2 253 50
7 262 160 5.6 303 0 stop
8 243 173 3.1 276 65 start cruise
9 247 187 17.6 277 65
10 248 197 17.4 283 65
11 254 208 14 288 69
12 257 213 15.6 291 64
13 259 218 18 296 65
14 261 225 14.7 298 65
15 262 229 15 300 65
16 266 234 16 303 54
17 262 234 18 302 54
18 264 234 16 302 54
19 262 234 13 298 62
20 264 236 17 302 62
21 266 239 14 303 62
22 268 241 14.2 303 66
23 294 234 15 349 0 stop/idle
24 291 232 14.4 345 0 idle
25 300 234 14.4 352 0 idle
26 300 234 13.4 345 0 start
27 270 241 14.2 305 70 accel to speed
28 300 244 5.2 342 slow on freeway
29 271 244 15.2 309 62
30 278 246 15.5 314 54 traffic
31 271 246 16.6 309 54
32 272 246 15 310 54
33 271 246 13 309 54 stable
34 268 246 11.8 305 68
35 275 248 13.9 309 70
36 277 250 12 312 70
37 278 253 13.7 312 70
38 278 256 13.6 315 70
39 280 257 12.9 317 70
40 280 258 13.3 317 70
41 282 262 18.8 324 exit Willis Rd
42 281 260 17.4 362 0 stop
43 284 255 15.4 319 45 cruise
44 280 251 16.4 316 50
45 278 250 18.5 314 48
46 275 248 17.6 309 46
47 275 244 21 312 48
48 282 241 17 331 0 stop
49 303 241 17.4 349
50 298 241 17.5 340 0 idle


Here are the graphs that we got from the data logger Starting out with the fan specs.



Let's get right to the meat of things, here is the time line of things happening.

Time Line of Fan plots, Reg and Elec

Stock mechanical fan

0 to 8 min cruise about 45 to entrance freeway

8 to 23 min cruise at 65 mph, some traffic

24 min idle on ramp for return

25-41 return on freeway, 55-70 mph

42 min exit freeway

43-49 min return shop 45-50 mph

Electric Fan Time Line

0-8 min Leave shop, cruise 45-50 mph to freeway

9-15 min Cruise freeway, 65 mph, had to stop because
Temp/pressure overtemp warning

16-18 min Let car idle to cool off

20-30 min Slow down to 50-55 mph

31 min exit freeway, return side roads, some knock

31-34 min Let idle to cool

35-56 min Cruise 45 on back roads to shop

58 min Raise speed to 60 mph, got Temp/Press overheat

58-60 Let idle to cool

61-77 Return to shop at 45 mph, Oil light on at idle
Found thermostat blown up from overheating.

Ambient temp: Reg fan: 80 deg F, Elec fan: 80 deg F start, 65 deg end

There is more available here. Yahoo Groups Fastvair

Now can we put the electric fan to rest? There is not a commercial electric cooling fan out there that can give the pressure needed, YES pressure, needed to cool the Corvair engine. OK, OK, there are fans out there but the power required to drive them is not economically feasible with the Corvair engine.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: Electric Fan, AGAIN
Posted by: 66vairman ()
Date: December 14, 2017 08:34AM

"Now can we put the electric fan to rest? There is not a commercial electric cooling fan out there that can give the pressure needed, YES pressure, needed to cool the Corvair engine. OK, OK, there are fans out there but the power required to drive them is not economically feasible with the Corvair engine."

That is a very good summary Ken.

I'm an electrical guy and in the old days computer equipment required a LOT of cooling. I learned fan CFM specs. are worthless if they don't come with a pressure gradient chart.

Recently I was looking at A/C condenser fans with some HUGE CFM numbers, but after some work I found the CFM dropped considerably at a low 2PSI above atmospheric pressure on the output side.

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Re: Electric Fan, AGAIN
Posted by: Bob Helt ()
Date: December 14, 2017 08:53AM

THANK YOU KEN for a great reminder. You and Frank did all the work and ran these tests. I remember it put a huge load on your shoulders at a bad time but you both completed the testing and final report. It was an amazing milestone.

66vairman,
Thank you for pointing out that it takes pressure to move air. That point is frequently missed (or ignored) whenever CFM is brought up.

As you said, Let's hope that this puts the subject to bed for good.
Bob Helt

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Re: Electric Fan, AGAIN
Posted by: davemotohead ()
Date: December 14, 2017 09:15AM

Fixed it! smoking smiley





Email me at: Dave Motohead

1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)




Sign my guest book!
[motoheadmall.com]
-----------------------------------
Rust Free Lancaster Ca

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Re: Electric Fan, AGAIN
Posted by: larry cooper ()
Date: December 14, 2017 09:19AM

Very interesting report and I had wondered about electric fan cooling. I will throw out my idea, however I have never tried it. I would request any critique.
I has been proved that a "squirrel cage design" puts out more air than a blade type fan. My thought, mount 2 (two)electric squirrel cages, one on each side of the engine compartment, duct air to top of each side of the engine. Probably the metal work on the engine would have to be altered. Your take ??? Larry Cooper

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Re: Electric Fan, AGAIN
Posted by: gnvair ()
Date: December 14, 2017 09:25AM

How about an electric fan attached to the stock fan?

Lee J

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Re: Electric Fan, AGAIN
Posted by: azdave ()
Date: December 14, 2017 09:31AM

gnvair Wrote:
-------------------------------------------------------
> How about an electric fan attached to the stock
> fan?

A friend installed this e-fan setup in his Corsa 180. He seriously overheated the engine a few month ago and is now back to running the stock system.


Dave W. / Gilbert Arizona
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed
65 Corsa 140 4-speed
66 Corsa 455 Toronado V8
65 Monza 455 Toronado V8
65 Monza 4dr 140 PG w/factory A/C
65 Monza 4dr EJ20T w/5-speed
66 500 4dr 110 3-speed Display Vehicle




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Re: Electric Fan, AGAIN
Posted by: gnvair ()
Date: December 14, 2017 09:35AM

What was the issue with the electric motor? Not able to spin the fan fast enough. You would think if you could get 2500-3000 rpms out of it then it would be do-able. What kind rpm did that set up spin? Did he check the fan speed?
Not playing devil's advocate; just curious.

Lee J

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Re: Electric Fan, AGAIN
Posted by: jjohnsonjo ()
Date: December 14, 2017 09:38AM

One thing I did not read, please correct me if missed it, Automotive alternators are about 60% efficient and the higher the load the worse it gets. Electric motors are about 90% or so. More modern alternators and motors are getting better. So when you go from mechanical to electrical energy then back again you will have losses the do not exist when you stay with mechanical. If you could produce the same air flow with an electric it could take up to twice the horse power off the crank.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

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Re: Electric Fan, AGAIN
Posted by: cnicol ()
Date: December 14, 2017 09:45AM

gnvair Wrote:
-------------------------------------------------------
> What was the issue with the electric motor? Not
> able to spin the fan fast enough. You would think
> if you could get 2500-3000 rpms out of it then it
> would be do-able. What kind rpm did that set up
> spin? Did he check the fan speed?
> Not playing devil's advocate; just curious.

The major issue is reversion. Rather than air going into and through the engine, it bounces back and flows out the large openings between the fan blades. That's why they don't build pressure.

At the Tacoma convention, I had an interesting conversation with a guy successfully running an electric fan. After initial failure with a single fan, he found a solution using two stacked, counter-rotating fans. Stacked counter-rotating fans stopped reversion.

Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
61 Seamist Jade Rampside 140 PG
60 Monza coupe (sold, sniff sniff)
66 Sprint Corsa convt - First car! Re-purchased 43 years later
2+2 gnatsuM 5691

+17 Tons of parts

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Re: Electric Fan, AGAIN
Posted by: MattNall ()
Date: December 14, 2017 09:52AM

That's Eddie Perez... the car that has been driven from Portland to the Toss.

Sadly, he also uses several other mods...





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo




Edited 1 time(s). Last edit at 12/14/2017 10:25AM by MattNall.

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Re: Electric Fan, AGAIN
Posted by: vairmech ()
Date: December 14, 2017 10:01AM

I still have the original set up that was tested but I can't find any photos of it installed on the test car, I know I took some.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: Electric Fan, AGAIN
Posted by: viewmaster ()
Date: December 14, 2017 10:06AM

MattNall Wrote:
-------------------------------------------------------
> That's Eddie Perez... the car that has been
> driven from Portland to the Toss.
>
> Sadly, he also uses several other mods...


"Sadly..."???? Tell more, Matt
-m



Mike
'65 '500' Sedan 110 PG
'65 Monza Sedan turbo'd 110 SU conversion
Fresno, CA



Edited 1 time(s). Last edit at 12/14/2017 10:26AM by MattNall.

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Re: Electric Fan, AGAIN
Posted by: BobV66Vair ()
Date: December 14, 2017 10:09AM

thumbs upthumbs up First, a big thank you to the team who did this real testing. It was clearly a lot of work. It is a little hard to know why it took so many decades for a fan to become available. Electric fans were around decade ago. Maybe the old racers found out how to keep their engines cool! I too know someone who swears by his electric fan but has no real data on it.

Porsche tried to solve the heat problem by using BIG vertical fans driven by the crankshaft but still went to water cooling. Racers of Corvair's still convert to using vertical fans but I have never heard/seen real testing to see if all that modification was worth it. A friend out here ran a stock fan with no bottom shrouds while racing and never had an overheating problem. He did rig up a fan for the pit that pulled air up through the engine rather than trying to push it. The idea was to cool after the engine/fan stopped.

I am intrigued by the squirrel cage idea but again, is it a solution for a problem most will never run into? Even racers seem to be able to cool their engines at high RPM using a stock fan.

Bob Vinnacombe
Sandy, Oregon
1965 Corsa 140 stock
1966 Monza Soon to be race car
1968 Monza Parts for now

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Re: Electric Fan, AGAIN
Posted by: gnvair ()
Date: December 14, 2017 10:22AM

Brian O'Neil I believe had a set up on his car. I have a picture of it at home. It used a large electric motor to drive the stock fan. Not sure how it worked for him.

Lee J

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Re: Electric Fan, AGAIN
Posted by: martyscarr ()
Date: December 14, 2017 10:30AM

"Brian O'Neill's unique electric cooling fan setup, powered by a high-capacity Volkswagen A/C motor."

From this page

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Re: Electric Fan, AGAIN
Posted by: MattNall ()
Date: December 14, 2017 10:33AM

viewmaster Wrote:
-------------------------------------------------------
> MattNall Wrote:
> --------------------------------------------------
> -----
> > That's Eddie Perez... the car that has been
> > driven from Portland to the Toss.
> >
> > Sadly, he also uses several other mods...
>
>
> "Sadly..."???? Tell more, Matt
> -m

Read / see all that's ever been posted here!





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: Electric Fan, AGAIN
Posted by: martyscarr ()
Date: December 14, 2017 10:45AM

Mel Francis used an electric motor to drive the fan in his Monza SS clone. I don't know how well it worked out for him.

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Re: Electric Fan, AGAIN
Posted by: cepak ()
Date: December 14, 2017 02:44PM

I remember asking questions about Electric fans on VirtualVairs back in 2003 and I
got absolutely hammered by several members on that email chain. Shortly
afterwards I had myself removed from the email list.


Tom Cepak
Fort Worth, TX

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Re: Electric Fan, AGAIN
Posted by: vairmech ()
Date: December 14, 2017 04:26PM

BobV66Vair Wrote:
-------------------------------------------------------
> First, a big thank you to the team who
> did this real testing. It was clearly a lot of
> work. It is a little hard to know why it took so
> many decades for a fan to become available.
> Electric fans were around decade ago. Maybe the
> old racers found out how to keep their engines
> cool! I too know someone who swears by his
> electric fan but has no real data on it.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>.>

The testing that I posted was done in 2006-2007.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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