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Current Page: 2 of 3
Re: Engine bay pressure tests on an early
Posted by: 63turbo ()
Date: June 07, 2019 06:59PM

Same conditions as for the stationary test above, for head temps and air temps
this time with lid safely tied down to 2" block at rear of lid, with car at
2250 rpm and 50mph, the engine bay pressure = +.25- +.27. the pressure rose and fell with car speed in a consistent manner, the peak pressure I read was
+.35 sadly I didn't get a read on either the rpm or the speed this happened at.
it was "probably" around 60.

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

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: Engine bay pressure tests on an early
Posted by: 63turbo ()
Date: June 08, 2019 06:29PM

Next test is to lift the front part of the lid, and leave the back down and latched... the front was raised roughly 1/2". Same conditions as the other tests.

at 50 mph, engine bay pressure= +.25"

when parked, I did a stationary test at 3k and noticed that the losses were
a bit worse than the previous test with the rear portion of the lid lifted
2", so this seemed to mean that the positive angle was helping, the limited
area was hurting, so the next easiest thing to try was blocking the rear of
the lid the same amount.

Testing it this way, entire lid lifted approximately 1/2",
at 50 mph, the engine bay pressure= +.30", although the numbers seemed to
be a bit more inconsistent.


To summarize the results so far at the same 50 mph:
stock (lid down)= +.2"
2" lift at rear only= +.25"
1/2" lift at front only=+.25"
lift whole lid 1/2" = +.3"

These are tiny gains, but the gain is 50% for lifting the whole lid 1/2"
and 25% for lifting only the front a small amount. It is clear that this
lifting of the lid business, while it has some value, seems to be a bit
over rated (at least at the heights I'm able to reasonably do), as the pressure gains are a tiny fraction of what should be possible if the intake caught as much wind as there is to get. I think my next set of tests will be to see how far over the fender the air intake would need to be to catch say 50% of the maximum. The idea being to perhaps have an actual hood scoop that
has its intake partially over the rear fender, so no hacking holes into the fender and body.
would

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

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: Engine bay pressure tests on an early
Posted by: American Mel ()
Date: June 08, 2019 08:41PM

Considering how thick the hood is(not the knife edge, but in where the bracing is) I would think that you would need to lift the front edge a good two inches before you would get any decent flow front lifting the front like a scoop.
Is the any Ram Effect involved at all?
Or is there constant vacuum in there?
What if you lifted the front 2 inches, and also made some small triangular side skirts on it so that it tended to trap air under the hood instead of allowing any to escape out the sides?

I think you are really onto something with the idea of collecting your air out in the unobstructed flow over the fenders.

.
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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
'67 A/C Moredoor Monza - 140 4-spd. driver
.
non-vair
'04 Dodge Cummins Quad Dualy, approaching 400K
17'Terry

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Re: Engine bay pressure tests on an early
Posted by: 63turbo ()
Date: June 08, 2019 09:01PM

It looks like there's some benefit to doing it, lifting the lid even more at the front, but sheesh, I didn't anticipate the hassles of doing this... I've
been out trying to re-align my deck lid for the past 2 hours just so it will latch half way close to normal. It just seemed like there is way more to be gained to creep the openings out over the fender than there is to try and catch every last bit of slow moving air. The openings wouldn't need to be as big, and only the deck lid would be messed with, and it might end up looking really cool if done right. I will say this, the engine did noticeably feel a bit more snappy when I raised the whole lid, probably from getting colder air, although I would bet you I could have gotten that effect by having a good heat shield on my turbo, instead of running it naked all these years!

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

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: Engine bay pressure tests on an early
Posted by: MattNall ()
Date: June 08, 2019 09:16PM

Kevin!! Just like Doors!! Drill a nail sized hole in each hinge BEFORE loosening...

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 06/08/2019 09:35PM by MattNall.

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Re: Engine bay pressure tests on an early
Posted by: MattNall ()
Date: June 08, 2019 09:38PM

Here's some FD sims that Greg Lloyd had made for his LM.... but I'll bet it's similar.

Attachments:

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How could this work??
Posted by: American Mel ()
Date: June 06, 2019 08:19AM

MattNall Wrote:
-------------------------------------------------------
> Here's Greg Lloyd's answer... Spent the $$ for the design. Feeds 3000cc... 600 cfm carb. Verticle fan.
>
> Placement most likely is the least drag with greatest Ram effect..




WoW!
That thing may work, but it is NOT the most attractive hood scoop I have ever seen. eye popping smiley
I think a N.A.C.A. duct on the side of each rear fender would be much more attractive.
I always wanted to do it, but at the same time did not want to cut up a perfectly good fender. grinning smiley hot smiley confused smileyeye rolling smiley
Maybe a good project for the coupe. eye rolling 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
'67 A/C Moredoor Monza - 140 4-spd. driver
.
non-vair
'04 Dodge Cummins Quad Dualy, approaching 400K
17'Terry



Edited 1 time(s). Last edit at 06/08/2019 09:43PM by MattNall.

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Re: Engine bay pressure tests on an early
Posted by: MattNall ()
Date: June 06, 2019 08:22AM

Mel... when trying to go 150 mph..... looks is second place... a distant second!! GGG

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: Engine bay pressure tests on an early
Posted by: American Mel ()
Date: June 09, 2019 12:00AM

Well, since you brought those posts over from the other thread, I will respond.
Since N.A.C.A. Ducts were developed for use on high speed jets, I still think they would be great candidates for use on a Landspeed Car.
You state that, . . . "Placement most likely is the least drag with greatest Ram effect.."
With N.A.C.A. Ducts, there is ZERO drag, just RAM EFFECT!
Those computer sims are really cool looking, though it appears that the focus on each of them is all about putting a scoop onto the hood.
There does not appear to be any flow sims regarding air flow over the ENTIRE car surface.
Do Landspeed rules limit intake scoops strictly to the hood?
I am curious, and would really like to see what the flow over the hind-quarters of the car is like at those speeds.
For that matter, I would really like to see Full-Body flow characteristics for an LM at the full range of "Normal" freeway speeds that us mere mortals drive, from 45 to 85+ MPH!
How much does the flow change as speed increases?

.
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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
'67 A/C Moredoor Monza - 140 4-spd. driver
.
non-vair
'04 Dodge Cummins Quad Dualy, approaching 400K
17'Terry

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Re: Engine bay pressure tests on an early
Posted by: MattNall ()
Date: June 09, 2019 07:30AM

A-mel... charts go from 20 -160 mph

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: Engine bay pressure tests on an early
Posted by: kdrolt ()
Date: June 09, 2019 07:38AM

The problem I see with the CFD simulation is that it doesn't show the flow reversals and/or vortices that occur for all passenger cars. To be more useful you would need the flow speed AND the pressure map. The actual aerodynamics are probably much more complicated than the simple CFD code can handle. Last point: the engine fan only draws max flow when the exh doors are fully open. And there is usually a low pressure region behind the car in the LM cove region. Corvairs have factory exh tips angled outboard to prevent recirculation of heated and engine exhaust gases. That's an effect not shown in the CFD sims.

Great topic btw. I'm a "fan" in spite of the comments.

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Re: Engine bay pressure tests on an early
Posted by: 66vairman ()
Date: June 09, 2019 08:10AM

stitch Wrote:
-------------------------------------------------------
> Has anyone tried punching vertical slot vents in both rear fenders (ala Wagon / FC style) for better breathability / pressure?. Might not look too out-of-place. Would prolly cool things down, on shut off, as opening the hood?...confused smiley

Someone around my area did. A LM convertible in primer. The slots in the side fenders looked AWFUL. Never did find out who drove the car and haven't seen it in some time.

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Re: Engine bay pressure tests on an early
Posted by: stitch ()
Date: June 09, 2019 08:16AM

66vairman sez:


Someone around my area did. A LM convertible in primer. The slots in the side fenders looked AWFUL. Never did find out who drove the car and haven't seen it in some time.

Maybe it was done 'Half Ass'!
I don't think Wagons or FC's look "Awful"!smoking smiley

"If you can't fix it with a Hammer, you have an Electrical problem."
Stitch...
Schertz, Texas.
(Smallish town/burg 17 mi. NE of San Antonio)

'Ms Penny'
!967.. 4th body
8th off the line

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Re: Engine bay pressure tests on an early
Posted by: 63turbo ()
Date: June 09, 2019 08:22AM

Mel- There's none, or very little ram effect with NACA ducts. They are, however very low drag inlets. The original name for these types of inlets were called "submerged inlets". Here's more than you probably ever wanted to know
on these [en.wikipedia.org].

I got to see the sims soon after they were posted on FB, and these are very interesting, as they do show clearly what many have said in the past about the LM air intake... it really is a bad location, and the yenko flaps also cannot work very well for the same reason. The simulation shows that the velocity is ZERO where the LM intake is placed, at 150 mph! If the inlet is operating that badly at 150, then it is just as ineffective at lower speeds, relative to the speed of the car. Yes, for land speed racing, hood scoops really are restricted to the hood, and apparently, creeping the scoop over the fender like I'm thinking about is called "channeling" and is banned... I don't care, though, I'm not going to be doing that! All I know is that for my fan, being able to take advantage of this ram effect further lowers the power that the fan consumes, and want to have some idea as to the pressure gains that can be expected for those that are tempted to go there! Something interesting about that Ram effect when being applied to the cooling system: If careful the overall drag on the car can net out to zero, or be even SLIGHTLY positive, because the extra air is being forced through the hot heads and exhaust which causes a dramatic expansion of the air which then leaves the exit much faster than it went in, causing a slight net thrust, from that source.

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

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: Engine bay pressure tests on an early
Posted by: American Mel ()
Date: June 09, 2019 06:58PM

MattNall Wrote:
-------------------------------------------------------
> A-mel... charts go from 20 -160 mph


Matt, I must politely disagree.
No, they do NOT show vehicle speeds from 20 to 160 mph.
They show the air flow changes going over a car that is going a steady 160 mph.
Places with good laminar air flow achieve 160mph flow(dark RED), while other areas (like the base of the rear window) have air flow speeds of less than 20 mph(dark BLUE).
I would like to see sims of airflow at normal driving speeds, ranging from 45 mph up to 85 mph.
I think that you would see a LOT of changes in the flow characteristics as the vehicle increases its speed.
While there is a negative pressure bubble at the back window, I would be willing to bet that it is extremely small at normal 55 to 65 mph freeway speeds.


kdrolt said, " And there is usually a low pressure region behind the car in the LM cove region. Corvairs have factory exh tips angled outboard to prevent recirculation of heated and engine exhaust gases. That's an effect not shown in the CFD sims."

Yes, it is shown in the 3rd sim picture that Matt posted.
Though it does not appear to be as big as the low pressure zone around the rear window.

.
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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
'67 A/C Moredoor Monza - 140 4-spd. driver
.
non-vair
'04 Dodge Cummins Quad Dualy, approaching 400K
17'Terry

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Re: Engine bay pressure tests on an early
Posted by: American Mel ()
Date: June 09, 2019 07:15PM

I must say that, I do not remember reading about this Salty guy when this stuff was originally posted.
I was not aware that his car was a LS racer when I made my comment about the looks of his scoop.
HUGE difference between us street guys(form over function) VS REAL racers where form follows function!
Now that I understand it true purpose, I can appreciate what it really is, and it acquires a certain beauty of its own, when viewed in its intended environment.
Is it something that I would install on my street car? NO ! ! ! spinning smiley sticking its tongue out

.
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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
'67 A/C Moredoor Monza - 140 4-spd. driver
.
non-vair
'04 Dodge Cummins Quad Dualy, approaching 400K
17'Terry

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Re: Engine bay pressure tests on an early
Posted by: 63turbo ()
Date: June 09, 2019 08:33PM

Preliminary test for ideal hood scoop locations today consisted of driving the
car at a steady speed with the pressure probe located roughly 1" out the driver side window, halfway between the "hip line" and the lower edge of the drivers side window... call it about the same location on the body as the "Bill Thomas" early scoops that were placed on the rear fender, except forward, as though they were placed on the drivers side door, with the probe
aimed dead straight into the wind.

Car speed Manometer reading

40 mph .7"
45 mph 1"
50 mph 1.22"
56 mph 1.65-1.7"

The outdoor air temps were right around 60 degrees again, and the above results are well within what is expected for velocity pressure at these
speeds, allowing for some experimental error.


Once I finished my measurements, which were done by holding the probe out the
window (in the specified spot) and reading the manometer, I proceeded to move
my hand as far back as I could out the window to see if I could feel any pressure changes with respect to the tested position, and I could not. To me,
this means that there is "probably" good clean air all along that hipline/top of fender area that is moving at actual velocity pressure for the car speed.
My next set of tests will have the pressure probe mounted back near the deck lid, and try to identify the spots as close to the hood and rear fender that will give the maximum/near maximum pressure for the car speed.

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

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: Engine bay pressure tests on an early
Posted by: American Mel ()
Date: June 09, 2019 08:47PM

Keep it up Kevin! thumbs upthumbs up
I don't even own an EM, but find this thread extremely interesting!
When you are finished with EM studies, maybe we can collaborate on LM dynamics.
I got the LM(multiple styles), you got the know-how and equipment.

.
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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
'67 A/C Moredoor Monza - 140 4-spd. driver
.
non-vair
'04 Dodge Cummins Quad Dualy, approaching 400K
17'Terry

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Re: Engine bay pressure tests on an early
Posted by: 63turbo ()
Date: June 09, 2019 10:05PM

Right on Mel, and thanks!smileys with beersmileys with beer I find this whole problem quite fascinating myself, and have learned a heck of a lot about actual real world fan testing and the real factors involved with fan output as the car is moving down the road, which is the most relevant, realistic way that can be done... and is the hard way to do testing, especially when I have to take data by myself, AND not hit the numerous deer that seem hell bent on going down in a blaze of glory because they suddenly like the other side of the road!!! This is the reason for
all the tests being done at such moderate speeds... gotta try and be safe you know!!

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

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: Engine bay pressure tests on an early
Posted by: American Mel ()
Date: June 09, 2019 10:10PM

Well, speeds are limited here to 30mph, but if I cross the border I can legally go as much as 100! grinning smiley eye rolling smiley hot smiley angry 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
'67 A/C Moredoor Monza - 140 4-spd. driver
.
non-vair
'04 Dodge Cummins Quad Dualy, approaching 400K
17'Terry

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