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Current Page: 4 of 5
Re: My New Fan!!
Posted by: American Mel ()
Date: June 18, 2018 08:38PM

You have us all wound-up like a bunch of kids on Christmas Eve! grinning smiley
We know Santa is coming, we just can't wait ! ! !

.
-----------------------------------------------
WA. state, 1 mile south of the Canadian border,
I am not at the end of the world, but you can see it from here.
'66 Monza Coupe - 4spd, 140 Daily driver beater
'67 Monza Vert. - PG, 140 Daily driver beater

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Re: My New Fan!!
Posted by: 63turbo ()
Date: June 21, 2018 08:01PM

Mel... A little tiny "Stocking Stuffer"smiling smiley I've tested the air-flow pulley as
shown in the picture, and I saw the same kind of small gain that I saw on the
test fixture. It also showed a slight loss at 5000 rpm, which always means that
the flow got a bit turbulent... this is understandable given all of the sharp
corners and 90 degree turns because of the mounting arrangement. The next test
will be a tapered cone that replaces the cylindrical spacers... I saw some nice
gains on the test fixture when trying this idea... that's what the red clay at the base of the pulley on the test fixture was all about.
Once I get the tapered cone spacer made and tested I will post the results, both with and without the bell.

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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Re: My New Fan!!
Posted by: MattNall ()
Date: June 21, 2018 08:32PM

Reading this last post, plus previous ones discussing the pulley...

I've wondered what the improvement would be if the Belt / pulley was eliminated!

The Wayne 100 flows tremendous air even when the OE '61-3 HD fan is replaced with a Mag Fan Cut down to 8"!! iirc.. [ fan had 2 broken fins ]

Stock pulley fits under fan.... just need to raise the fan bearing....to align pulley with belt....then build custom shroud to enclose fan at it's new height. Approx. 3-4" taller?



Edited 1 time(s). Last edit at 06/22/2018 07:41PM by MattNall.

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Re: My New Fan!!
Posted by: 63turbo ()
Date: June 21, 2018 09:39PM

It makes a lot of sense! the stock pulley represents 30% of the total area
of the intake, and worse than that is the odd path the air has to take...
the curve at the base of the fan is pretty much defeated by the path. There
was a presentation on cooling fans by some engineer in the 60's for an SAE
paper... although he did not state the brand of engine he was talking about,
the shape of the fan with the pulley on it made it clear he was talking about
the then new Mag fan for the Corvair… he did seem to be aware that the fan
pulley was a blockage. One of the Corvair clubs posted that article in their
monthly newsletter, although I cant remember which newsletter it was, or the
date.
There's a way to estimate the drag coefficient for a fan with a pulley near
the intake, and it is based on how much area the pulley consumes vs the total
area... I used that technique on the corvair intake system... the drag coefficient that I came up with for the stock set-up was 1, and a pulley vented
like mine would have a drag coefficient of .1 so that the losses from the size
would be 1/10 as much, or the losses with the stock set-up would be 10 times worse!!

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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Re: My New Fan!!
Posted by: caroseiii ()
Date: June 22, 2018 11:34AM

Can't one grind off four slices of the bottom of the stock pulley to net the same effect?

Crawford

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Re: My New Fan!!
Posted by: American Mel ()
Date: June 22, 2018 01:16PM

Hmmmmm.
Kevin this question seems familiar. winking smiley

.
-----------------------------------------------
WA. state, 1 mile south of the Canadian border,
I am not at the end of the world, but you can see it from here.
'66 Monza Coupe - 4spd, 140 Daily driver beater
'67 Monza Vert. - PG, 140 Daily driver beater

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Re: My New Fan!!
Posted by: 63turbo ()
Date: June 22, 2018 06:25PM

caroseiii Wrote:
-------------------------------------------------------
> Can't one grind off four slices of the bottom of
> the stock pulley to net the same effect?
>
> Crawford

Yes, you can modify the stock pulley, no you cant get the same net effect. The reason is that the pulley gets weakened if you take too much off. I figured
that 2 square inches worth of holes is probably a reasonable maximum that can be taken out without running into breakage problems. The other thing is that
it is hard to modify the stock pulley because it is steel and is hard to reach
the spots that need to be opened without hitting the lower sheave, because of the shape. 2 square inches is roughly a 6% area gain though, and is worth doing.

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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Re: My New Fan!!
Posted by: jjohnsonjo ()
Date: June 23, 2018 08:30AM

I guess if I wanted to open it up, I would drill a bunch of smaller holes and chamfer the edges. Might not be as much area, but you would still retain a lot of strength. If that's a bad idea Kevin, let me have it.

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: My New Fan!!
Posted by: 63turbo ()
Date: June 23, 2018 09:27AM

jjohnsonjo Wrote:
-------------------------------------------------------
> I guess if I wanted to open it up, I would drill a
> bunch of smaller holes and chamfer the edges.
> Might not be as much area, but you would still
> retain a lot of strength. If that's a bad idea
> Kevin, let me have it.

No, it is not a bad idea at all, far from it. When I was testing this idea on
my fixture, that was exactly how I did it. The flow kept increasing as the open area increased... it seemed like up to roughly 2 square inches worth of
opening the flow increased, but even larger openings appeared to cause the flow
to drop, but adding a bell and or adding clay in the right spots caused disproportionate gains that couldn't be explained by the bell by itself or the
pulley by itself. When my pulley was opened up to the point where these losses
could appear if not careful (clay on inside next to bearing, clay on lower part of sheave and bell on), the pulley was way past the point of being strong
enough to actually use on the car. 2 square inches is roughly 8 holes .56"
in diameter... if these are evenly divided around the pulley it will be strong
enough. It may actually work better if the edges of the holes could somehow be
tweaked so that the trailing edge of the hole is aimed inwards towards the bearing, and the leading edge of the hole is bent outwards towards the lower
sheave.

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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Re: My New Fan!!
Posted by: MattNall ()
Date: June 23, 2018 10:52AM

I THINK youen you get too much open... of the wrong shape.... you cause turbulence?





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
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Re: My New Fan!!
Posted by: American Mel ()
Date: June 23, 2018 11:54AM

Yes Matt.
"The flow kept increasing as the open area increased... it seemed like up to roughly 2 square inches worth of
opening the flow increased, but even larger openings appeared to cause the flow
to drop, . . . ."


.
-----------------------------------------------
WA. state, 1 mile south of the Canadian border,
I am not at the end of the world, but you can see it from here.
'66 Monza Coupe - 4spd, 140 Daily driver beater
'67 Monza Vert. - PG, 140 Daily driver beater

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Re: My New Fan!!
Posted by: 63turbo ()
Date: June 23, 2018 11:55AM

MattNall Wrote:
-------------------------------------------------------
> I THINK youen you get too much open... of the
> wrong shape.... you cause turbulence?

Absolutely! this may be more of a problem modifying an aluminum pulley that
has a flat bottom on the lower sheave than modifying the stock steel one, they
are different that way... the lower sheave on the stocker is aimed more downward- I never tested this idea on a stock pulley so I don't know for sure.
This is the reason for the dam/skirt thing on my custom pulley. It still wont
flow what it is capable of until the round spacers are replaced with a cone
shaped thing.

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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Re: My New Fan!!
Posted by: American Mel ()
Date: June 23, 2018 12:05PM

63turbo Wrote:
-------------------------------------------------------
> MattNall Wrote:
> --------------------------------------------------
> -----
> > I THINK youen you get too much open... of the
> > wrong shape.... you cause turbulence?
>
> Absolutely! this may be more of a problem
> modifying an aluminum pulley that
> has a flat bottom on the lower sheave than
> modifying the stock steel one, they
> are different that way... the lower sheave on the
> stocker is aimed more downward- I never tested
> this idea on a stock pulley so I don't know for
> sure.
> This is the reason for the dam/skirt thing on my
> custom pulley. It still wont
> flow what it is capable of until the round spacers
> are replaced with a cone
> shaped thing.


What exactly do you mean when you say cone shaped?
I keep trying to picture a cone in there, and am just not getting it.
Narrow at the top?
Narrow at the bottom?
Narrow on the outside/wide at the back near the bearing?
The last one there seems to make the most sense to me, just think the wording is messing me up.

.
-----------------------------------------------
WA. state, 1 mile south of the Canadian border,
I am not at the end of the world, but you can see it from here.
'66 Monza Coupe - 4spd, 140 Daily driver beater
'67 Monza Vert. - PG, 140 Daily driver beater

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Re: My New Fan!!
Posted by: 63turbo ()
Date: June 23, 2018 12:53PM

Basically, the cone shaped thing has a slip fit over the bearing, and is wide at the bottom where it contacts the fan, and tapers towards the top of the bearing. The pulley sets at exactly the same height as it does now, so the cone
has to have slots in it to accommodate the "lugs" on the pulley mounting points. Anyways, skinny towards the top of the bearing o.d., fat at the fan.
I'm sure it will be easier to visualize after I take a picture of itsmiling smiley

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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Re: My New Fan!!
Posted by: American Mel ()
Date: June 23, 2018 01:52PM

OH!
I think I get it now.
Similar in idea to the small cone that is currently sold to go on-top of the bearing.
Only your's will be covering the bearing and incorporate the pulley support!
It will help guide the air-flow outwards as it comes down from above.
WoW!
This whole set-up is quite the piece of engineering!
No wonder GM said, "Eeh, this is good enough."

.
-----------------------------------------------
WA. state, 1 mile south of the Canadian border,
I am not at the end of the world, but you can see it from here.
'66 Monza Coupe - 4spd, 140 Daily driver beater
'67 Monza Vert. - PG, 140 Daily driver beater

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Re: My New Fan!!
Posted by: 63turbo ()
Date: June 23, 2018 05:12PM

American Mel Wrote:
-------------------------------------------------------
> OH!
> I think I get it now.
> Similar in idea to the small cone that is
> currently sold to go on-top of the bearing.
> Only your's will be covering the bearing and
> incorporate the pulley support!
> It will help guide the air-flow outwards as it
> comes down from above.
> WoW!
> This whole set-up is quite the piece of
> engineering!
> No wonder GM said, "Eeh, this is good enough."

You got it Mel!smileys with beer

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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Re: My New Fan!!
Posted by: jjohnsonjo ()
Date: June 23, 2018 05:24PM

63turbo Wrote:
-------------------------------------------------------
> American Mel Wrote:
> --------------------------------------------------

> > No wonder GM said, "Eeh, this is good enough."
>
>Sad thing is GM had the engineering to do it, as well mass producing something similar with a casting that would have not cost all that much.

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

Image and video hosting by TinyPic

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Re: My New Fan!!
Posted by: American Mel ()
Date: June 23, 2018 06:59PM

63turbo Wrote:

You got it Mel! smileys with beer

Duh. eye rolling smiley
For some reason I misunderstood what you were saying and was trying to picture FOUR little cones tucked in there supporting the pulley. confused smiley

.
-----------------------------------------------
WA. state, 1 mile south of the Canadian border,
I am not at the end of the world, but you can see it from here.
'66 Monza Coupe - 4spd, 140 Daily driver beater
'67 Monza Vert. - PG, 140 Daily driver beater

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Re: My New Fan!!
Posted by: 63turbo ()
Date: July 07, 2018 09:45AM

Here's some pictures of the "cone shaped spacer thingy", which ended up
not cone shaped, but curved... I must have changed my mind on this part three
or four times, but after doing a Solidworks model and creating a assembly
of the fan, pulley, and spacer, it became clear that the right shape for the
lower spacer should be a arc of some sort. I had a heck of a time making this
part because of issues clamping it after the arc was formed, and turned out not being practical for me to make it as a one piece thing... the 4 cylindrical
spacers were shortened and counter bores were cut into the larger arc spacer.
This piece would be simple to do on a CNC machine, as all 5 spacer pieces could be made as one part.

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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Re: My New Fan!!
Posted by: 63turbo ()
Date: July 07, 2018 12:09PM

I just got done testing this... I got a 10% increase in pressure, and a 5% increase in flow, and this difference stayed pretty consistent out to 4k,
although the 5k number remained roughly the same. It might be that there's still some turbulence, but it may also be that there's starting to be a bit of
belt slippage. In any event, it was quite a surprise to see such a large change
in the numbers simply from changing the shape of the spacer... the original 4 cylindrical spacer arrangement changed the pressure approximately 6% and the flow 3%. These gains might not seem like much, but the impact on the "air horsepower" for the improved spacer and airflow pulley (which effects the efficiency of the fan), was changed 15%...
a change like that is enough to move the peak efficiency to 65% from 56%, if the drive horsepower didn't change. A big if for sure but it would be odd if
the drive horsepower went up proportionate to the air horsepower change, as this did not happen in my tests on the test fixture. It will be interesting to see how this current airflow pulley works when the bell is added.

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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