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Bell Mouth #4!!!
Posted by: 63turbo ()
Date: June 24, 2019 07:59PM

I just got my new bell mouth today. I have been wanting to try this out for so long! This is the guide vane version of my "big" bell mouth, and if it works out well ought to push the efficiency of my fan over the top, as guide vanes added to a well optimized bell can increase the efficiency another 5-8% over a "standard" bell. It is going to be seriously interesting to see how this thing works!

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

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



Attachments:


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Re: Bell Mouth #4!!!
Posted by: American Mel ()
Date: June 24, 2019 08:10PM

Kevin, could you please explain these guide vanes a bit?
Because the first thing I see here is that they are tilted in a direction that is completely counter intuitive to someone like me who is not an Air-flow Dynamics Engineer such as yourself.

-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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.
Have; '66 Monza Coupe - 140, 4-spd. Daily driver beater
'67 Monza Vert. - 140, 4-spd. Daily driver beater
'67 A/C Moredoor Monza
Have had; '61 Monza coupe, '62 Monza Wagon, '63 Spyder, '65 Corsa
.
non-vair
'04 Dodge Cummins Quad Dualy, approaching 400K
17'Terry

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Re: Bell Mouth #4!!!
Posted by: 63turbo ()
Date: June 24, 2019 08:44PM

Guide vanes are basically a method to speed the air up without making the hole smaller. You can see that the edges of the vanes are closer together on the bottom than they are at the entrance, and this is where the speed comes from. Some inlet guide vanes are simply straight up and down, and those are used in cases where the intake air is spinning as it goes in. Any time this spinning condition exists, the fan is running in a inefficient state, and is not that different from a propeller spinning in water, and the water is rotating with the propeller. I got the idea to try the blades angled like that
from someone over at facebook and did some research on it online. After reading up on the study's that I found it was clear to me to rake the blades like that. Easiest way to think about it is that having the vanes tilted like they are, better matches the blade angle of the fan at that point, and encourages the air to come in at a more favorable angle to the blades on the fan.

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

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: Bell Mouth #4!!!
Posted by: American Mel ()
Date: June 24, 2019 08:56PM

WELL, . . . . . HURRY UP AND GET IT INSTALLED ! ! ! grinning 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.
Have; '66 Monza Coupe - 140, 4-spd. Daily driver beater
'67 Monza Vert. - 140, 4-spd. Daily driver beater
'67 A/C Moredoor Monza
Have had; '61 Monza coupe, '62 Monza Wagon, '63 Spyder, '65 Corsa
.
non-vair
'04 Dodge Cummins Quad Dualy, approaching 400K
17'Terry

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Re: Bell Mouth #4!!!
Posted by: vairmech ()
Date: June 25, 2019 04:39AM

All you need to know and maybe understand is go look at a multi stage turbine engine. The static vanes are angled just like you see here to optimize the angle of the air entering the rotating blade.

Tubine Engine Stator Vane Angles

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: Bell Mouth #4!!!
Posted by: 63turbo ()
Date: June 25, 2019 06:31PM

That's one way they are used... in centrifugal fans they are also used to "throttle" the fan, using guide vanes that have a variable angle, and
can run the fan more efficiently during times of low air demand.
I found though, that there are significant efficiency benefits for systems that use a fixed angle.

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

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: Bell Mouth #4!!!
Posted by: American Mel ()
Date: June 26, 2019 05:37PM

It has been 48 hours now Kevin!
What's the hold-up?
We NEED results ! ! !
grinning smiley grinning smiley grinning 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.
Have; '66 Monza Coupe - 140, 4-spd. Daily driver beater
'67 Monza Vert. - 140, 4-spd. Daily driver beater
'67 A/C Moredoor Monza
Have had; '61 Monza coupe, '62 Monza Wagon, '63 Spyder, '65 Corsa
.
non-vair
'04 Dodge Cummins Quad Dualy, approaching 400K
17'Terry

Options: ReplyQuote
Re: Bell Mouth #4!!!
Posted by: 63turbo ()
Date: June 26, 2019 08:13PM

American Mel Wrote:
-------------------------------------------------------
> It has been 48 hours now Kevin!
> What's the hold-up?
> We NEED results ! ! !
> grinning smiley grinning smiley grinning smiley

Patience young grasshopper... all in good timesmiling smiley. Actually, I've been moving as
fast as I can on it without screwing up! this is super exciting stuff for me, especially after re-reading the study I had originally looked at to help me figure the angles out, and remembering some of my earlier test's that I did that didn't work out as well as planned. The spinning intake might explain what was going wrong! all of the better tests came from making the fan shroud hole smaller, and this by itself always reduces spin... going to a bigger hole
always made the peak pressure lower. HMMM!!!

And yes I know you are just kiddingsmiling 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: Bell Mouth #4!!!
Posted by: 63turbo ()
Date: June 26, 2019 08:56PM

Update #1 for the guide vane bell: The vanes appear to be working as intended in the sense that whatever tendency I was seeing in the past for the air to spin (using strips of paper) has been entirely eliminated, and the air also does seem to be following the vane angles into the fan, which is a seriously good thing to be seeing! The other observation was the pressure kept climbing at the same 1000 rpm as read off the SDS display as the engine got warmer. By the time I shut the engine down, the pressure at 3k was 5.5", and the doors were just starting to open, and the pressure at 1000 rpm went from .55" when I first started it up to over .7". Pretty interesting to see that, but I don't have any comparative data on what pressures I should be seeing with the doors mostly shut and warming up. Real testing to start tomorrow, when I can get out and drive it and have a chance to get the doors to open!

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

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: Bell Mouth #4!!!
Posted by: chuckvh ()
Date: June 27, 2019 05:05AM

Kevin
Any update on the new fan production status?

Chuck vonHofen
Brentwood, California

66 Corsa Turbo Convertible
64 Spyder Convertible
64 Spyder Coupe
62 Monza Convertible
Amazingly Patient Wife

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Re: Bell Mouth #4!!!
Posted by: 63turbo ()
Date: June 27, 2019 07:34PM

chuckvh Wrote:
-------------------------------------------------------
> Kevin
> Any update on the new fan production status?


Hi Chuck- unfortunately, I don't have any new information on that, other than
as of a week ago, they are in the planning stages. Once they start making chips I hope to get pictures up here to show the machining of the fans as it happens. I really seriously appreciate your patience!

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

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: Bell Mouth #4!!!
Posted by: 63turbo ()
Date: June 30, 2019 02:48PM

The guide vane bell appears to be making some real wind! Its weird but it has gotten hard to get the head temps over 300f. Before I had put this on, by the end of a 10 mile trip at a steady 45-50mph, the heads would just touch 300, running 14.5-15.5:1 a/f. When I put the new bell on, the same conditions and driving, the heads will run at 280 for the entire trip. The measured pressure's so far... 8.5" to 9" at 4k engine rpm, 5.3" at 3k engine rpm, and around 2.5" at 2k... I believe these are an indication that the damper doors aren't fully open, but these numbers were obtained with hotter weather, more aggressive driving and were taken with the head temps about as close to 300 as I've been able to do so far. I might have to resort to blocking the damper doors open and spin the fan with a Dremel and record the pressures and fan rpms with the three bells that I have to make the comparisons more clear and accurate. It sure seems to be blowing the doors off anything else I've tried so far!!

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

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: Bell Mouth #4!!!
Posted by: joelsplace ()
Date: June 30, 2019 03:44PM

Exciting stuff!

Joel
Northlake, TX
5 Ultravans, 114 Corvairs and counting...

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Re: Bell Mouth #4!!!
Posted by: 63turbo ()
Date: July 03, 2019 04:26PM

Thanks Joel! I just completed my first somewhat controlled experiments using a Dremel tool to spin the fan, recording the rpm and pressure with the damper doors blocked open and it looks like the guide vane bell is 12% more efficient than my "small" bell and 7% more efficient than my non guide vane bell with exactly the same shape and overall dimensions, and all three bells were more efficient than no bell. Kind of crazy to see that big of an improvement, and I don't quite trust it yet, but for now, I will take it as a sign that I'm on the right track, and will be getting to actual drive hp measurements on the car with the new bell later this week, using a more sensitive technique than I was able to do before.

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

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: Bell Mouth #4!!!
Posted by: jjohnsonjo ()
Date: July 03, 2019 06:24PM

Kevin, I am also following this with great interest, thanks for the updates. Need to try to see this stuff in person next time I visit our son in Seattle.

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: Bell Mouth #4!!!
Posted by: jjohnsonjo ()
Date: July 04, 2019 07:11PM

Hi Kevin, another thread about total cooling capacity got me wondering. Have you converted any of your CFM numbers to BTU numbers. The bottom line question would be how close are you getting to net zero with a turbo engine running at full power. I guess I could do it myself since I did a lot of solar heating stuff way back in the 70s. Basically temp in plus fan generated temp, temp out and CFM.

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: Bell Mouth #4!!!
Posted by: 63turbo ()
Date: July 04, 2019 09:15PM

That one I don't know... theres lots of factors related to the fan set-up that effect the peak efficiency, and its width. For example, simply by making the intake smaller I can get a narrow range with a high peak, and with a bigger intake it might be wider with a peak efficiency at a higher rpm, or it may just be lower and wider. These are the kinds of things that can mess with the fan and how much heat is produced from pumping the air. I do know that with the stock fan, it is adding 50-60 degrees to the discharge temperatures before it goes into the heads at an engine rpm of around 5500- mine might be only adding 15-20 under the same conditions but a lot more airflow. I know for certain it is cooling really well, judging by how lean I can run it at freeway speeds and still see the heads at around 300-310. I think it would do even better if I had a heat shield for the turbo... It has never had one!

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

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: Bell Mouth #4!!!
Posted by: jjohnsonjo ()
Date: July 05, 2019 05:57AM

I don't have a turbo blanket, but I did wrap the inlet and outlet pipes within the engine compartment, plus some wrap on the turbo itself under the factory shield. Real easy to do and it dropped my highway temps. I also have a computer fan just above the heat shield that helps exhaust turbo heat after shutdown, which helps with heat so and restarts.

I'd say your fan isn't generating as much heat as the factory. Although I did get to wondering if there is a point at which the speed of the airflow over the heads when the absorbtion rates starts to decline.

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: Bell Mouth #4!!!
Posted by: 63turbo ()
Date: July 05, 2019 07:43AM

jjohnsonjo Wrote:
-------------------------------------------------------
>
>
> I'd say your fan isn't generating as much heat as the factory. Although I did get to wondering if there is a point at which the speed of the airflow over the heads when the absorbtion rates starts to decline.

The point at which the absorbtion rate starts to decline would be when there is no, or very little change in temperature between the ambient inlet temps and outlet temps... we are not even close to that point yet!!. Nearly all my testing has been done with the lower shrouds on, as best I can determine, the lower shrouds reduce the flow by 35-40%. The one time I took the shrouds off, I couldn't tell that the head temps had changed from dead cold... it was impossible to warm the engine like that. Not a good experiment to be doing in the middle of the winter!!! With a 140, when it is 80 degrees outside, and you are doing 80 mph, with the lower shrouds on, the heads get to around 380. With the lower shrouds off under the same conditions, the heads will only get to 300. My own experience with the stock fan and similar weather and operating conditions was roughly the same. It has not gotten hot enough around here for me to push it with the lower shouds off yet on the freeway, but my suspicion is that it will be very overcooled. There are some interesting tests planned for later this summer that will be very illuminating as to what the realistic cooling limitations are for a turbo running full tilt with my fan, with all the big cooling tricks applied. We will just have to wait and see!

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

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: Bell Mouth #4!!!
Posted by: 63turbo ()
Date: July 13, 2019 10:42PM

Epilogue to guide vane bell...

Better, more controlled tests with this bell showed some crazy huge pressure benefits... I saw as much as 9.5" at 4000 engine rpm with the doors open as far
as they were going to get, but it also became clear that it was using more power to do it than it should have. Since the bell diameter for that test was 8.5", and was by far the most intake area I had tested, and also because the engine was at risk of over cooling most of the time, I decided to test it at 7.9", and this would put the intake area at 37.5 square inches, which is only 1.5 square inches more than stock. My best hp estimate for that test is 7.2 hp
at around 4900 engine rpm- this is roughly 1.2 hp more than my earlier estimate of 6 at 5000 rpm, however, at 4900 rpm the fan was cranking out 13" and around 1777-1800 cfm at this rpm, and that would also put the hp 4 at 4000 engine rpm and 8.3-8.5" and roughly 1500 cfm...and were also large changes in pressure and flow over my earlier tests. The guide vanes accomplished one goal by making a large change in pressure but clearly reduced the efficiency.
The guide vane angles were good for one thing and bad for another. A simple test using a blow dryer to spin the fan with the damper doors blocked open and
monitoring the fan rpm with a laser tach showed that there was exactly one angle for the blow dryer that would cause the fan to spin the fastest, and every time I aimed the blow dryer similar to the guide vane angle, OR flip it the other way at the same angle resulted in a 22% loss in rpm. Since I was inputing the exact same energy into the fan with the blow dryer, and only changing the "angle of attack", the higher the rpm the more efficient the angle is because the fan is better able to "recover" this wind energy, so this test was a good way to sort out the revisions needed for the guide vane bell to up the efficiency of the fan... a lot!!

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

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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