[DeTomaso] Rear Window
Michael Shortt
michaelsavga at gmail.com
Fri Mar 18 11:57:11 EDT 2016
Stephen,
I would simply borrow, collect, rent a bunch of Go Pros,
you can sync them with audio cues (clap sticks)
and edit together a control panel video.
if you could do it on a race track, you could also overlay
info from an App like Harry's Race Timer.
I look forward to seeing your results, your research
methods seem intense and and very interesting.
Are you also going to measure engine CFM intake and air temps?
measure any performance loss, if any?
Knowing as a racer that cool air is better than war air, will you be
adding other cold air intakes or simply sucking it from the engine
area at whatever the amibient temp might be in all conditions?
Michael Shortt
On Fri, Mar 18, 2016 at 11:35 AM, Stephen <steve at snclocks.com> wrote:
> I've been pondering for quite a while now the idea of putting a piece
> of glass in the "window" in the deck lid behind the engine in 5332.
> This would keep the engine from getting wet every time it rains and
> would also keep from sucking grit and water off the road when the car
> is running down the road.
>
>
> Both seem like decent goals. Oh, and it would also make it more
> difficult for someone to just reach in and remove 5332's dog-bone air
> cleaner. OK - no one has taken it so far. But, hey, it would be all
> too easy to remove.
>
>
> Looking at the opening - it sure looks like the original intent was to
> put in a window.
>
>
> I have sent an e-mail to Tom Tjaarda (attached) asking his thoughts.
> Hopefully he will respond.
>
>
> In the interim, I put together a set of sensors so I could see what I
> could learn about conditions in the engine compartment just inches in
> front of the opening, to the right side of the dog-bone. The attached
> photo shows the instrument cluster shot from inside the car.
>
>
> I'm measuring air velocity through the rear window (vane anemometer)
>
> Vacuum just in front of the window
>
> Rotation of the a/c condenser fan (volt meter connected across the
> motor, which acts as a generator when the fan turns)
>
>
> Two of the above are fairly straight forward. The vacuum - not so
> much.
>
>
> When one talks about a vacuum, one is usually talking about a vacuum,
> relative to ambient atmospheric pressure. So, if a vacuum gauge is
> hooked up to your intake manifold, it reads the difference in pressure
> between the atmosphere where the gauge is sitting, and the inside of
> your manifold, where the hose from the gauge is connected.
>
>
> So, what does one compare to in a moving car? The interior of the
> car? That is what one would get if one puts a vacuum gauge in the cab
> and routes the hose to the area in question. But, what does the
> pressure (or vacuum) inside the car do with the car moving down the
> road. Open the windows, your ears pop, and the pressure changes. Most
> of us don't have an external air inlet (at least an intentional one) to
> the cab except for the windows.
>
>
> My solution is to use a fairly sensitive pressure gauge (a
> sphygmomanometer - gauge used to read blood pressure. It reads in
> inches of mercury. FYI, there are roughly 50 inches of mercury per
> psi). I have connected the gauge with small-diameter plastic tubing to
> a 200 ml stainless sample bomb. I wrapped the bomb in towels and
> placed in a cooler to minimize temperature changes. See, the pressure
> in the bomb will change by roughly .03 psi (1.5 mm Hg) for each 1
> degree F change in temperature.
>
>
> I then pressured up the bomb and let it sit overnight to stabilize. It
> ended up at 280 mm. This is my "zero" at the then current barometric
> pressure.
>
>
> One has to view the pressure gauge as a delta-pressure device. It
> shows the difference in pressure between the bomb (high pressure) and
> the atmosphere around the gauge. So, if the reading on the gauge goes
> up, the differential is increasing, which means the atmospheric
> pressure is going down. As in a wee bit of a vacuum around the gauge.
> Flip side, if the reading on the gauge goes down, well, there is less
> differential between the 280 mm Hg in the bomb and the atmosphere
> around the gauge, so the pressure is going up.
>
>
> OK - that is complex.
>
>
> While a gauge that can be read down to around 1 mm hg (0.02 psi) is
> pretty sensitive, I suspect we are talking pretty minimal vacuum
> levels. Preliminary testing suggested a reading of 272 mm Hg at 80
> mph. The pressure around the gauge went up!
>
>
> Huh. A lot to learn here.
>
>
> I also noted that the volt meter did not show any rotation of the fan
> on the a/c condenser. Need to make sure the wiring is ok. But, note,
> the meter reads in mV, and, in my earlier testing, it showed voltage if
> the fan turned at all.
>
>
> The rubber for the new window shows up today, the window next
> Wednesday.
>
>
> My plan is to get a decent video and stills of the test instruments at
> several speeds. Then, when the new window is installed, rerun the
> test. I suspect the anemometer will still be valuable, since I suspect
> there will be a lot of turbulence in the air in the engine compartment
> even with the window in place.
>
>
> Needless to say, having the window in place will complicate putting the
> deck-lid back in place.
>
>
> Stephen Nelson
>
>
> ---------- Forwarded message ----------
> From: Stephen <steve at snclocks.com>
> To: <tjaarda at astranet.it>
> Cc:
> Date: Tue, 15 Mar 2016 10:01:30 -0700
> Subject: Pantera Rear Window
> Good morning Tom. Whilst I am pretty sure you have no clue who I am,
> being a member of POCA, I am aware of your contribution to the
> Pantera. And I thank you for what you designed.
>
>
> Being fairly new to these cars (3 years) I am still learning a lot.
> One thing I have noted is the ability of my car to pick stuff up off
> the road when I am driving at speed. I have found 1/4 inch gravel
> behind the inlet manifold and was amazed to see high water marks on the
> side of the rocker covers after a couple of hours driving in the rain
> at 70 mph. Really quite neat actually, little wave pattern down the
> sides of the rocker covers. Should have shot a picture.
>
>
> None the less, I have queried the POCA forum about the absence of glass
> in the opening behind the top of the engine. Folks indicated no one
> had ever tried installing glass, and some voiced concerns about the
> cars overheating if there was not lots of air flow past the engine.
>
>
> So, am writing to see if I can get your thoughts on the lack of a
> window in the deck lid and would appreciate any wisdom you can impart.
>
>
> Whilst I have done a number of upgrades to 5332, including making the
> engine a wee bit stronger, installing the best radiator and fans that I
> could identify, and getting the a/c so it keeps the car comfortable, I
> haven't really made any changes in the aerodynamics - like wings or
> spoilers or front air dams. I suspect she would be a good test mule
> for such a window and plan to start my investigation by figuring out
> pressure (vacuum) levels above the engine at various speeds and also
> the direction of rotation and relative rpm of the a/c condenser fan
> (volt meter across the motor). My thought is to then do the same with
> a window in place.
>
>
> Any and all comments would be appreciated.
>
>
> Stephen Nelson
>
>
> [1]SNClocks.com
>
> Click here to join one of our mailing lists [2]Contact Lists
>
> Click here for our new [3]Hammered Dulcimers galleries
>
> Click here for [4]my new blog on finding happiness in retirement
>
> References
>
> 1. http://www.snclocks.com/
> 2. http://fs19.formsite.com/kagforms/form675003155/index.html
> 3.
> http://www.snclocks.com/TheRestofourWorld/Hammered-Dulcimers/About-Steves-Dulcimers/19824807_4sHGgj#1558377542_LKmkrT7
> 4. http://www.perfectoldman.com/
>
> _______________________________________________
>
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>
--
Michael L. Shortt
Savannah, Georgia
www.michaelshortt.com
michael at michaelshortt.com
912-232-9390
This email is protected by the Electronic Communications Privacy
Act, 18 U.S.C. Sec. 2510-2521, is confidential and may be legally
privileged. If you are not the intended recipient, you are hereby notified
that any retention, dissemination, distribution or copying of this
communication is strictly prohibited. Please reply to the sender that you
have received this message in error, then delete it. Thank you
-------------- next part --------------
Stephen,
I would simply borrow, collect, rent a bunch of Go Pros,
you can sync them with audio cues (clap sticks)
and edit together a control panel video.
if you could do it on a race track, you could also overlay
info from an App like Harry's Race Timer.
I look forward to seeing your results, your research
methods seem intense and and very interesting.
Are you also going to measure engine CFM intake and air temps?
measure any performance loss, if any?
Knowing as a racer that cool air is better than war air, will you be
adding other cold air intakes or simply sucking it from the engine
area at whatever the amibient temp might be in all conditions?
Michael Shortt
On Fri, Mar 18, 2016 at 11:35 AM, Stephen <[1]steve at snclocks.com>
wrote:
A A I've been pondering for quite a while now the idea of putting a
piece
A A of glass in the "window" in the deck lid behind the engine in
5332.
A A This would keep the engine from getting wet every time it rains
and
A A would also keep from sucking grit and water off the road when
the car
A A is running down the road.
A A Both seem like decent goals.A Oh, and it would also make it
more
A A difficult for someone to just reach in and remove 5332's
dog-bone air
A A cleaner.A OK - no one has taken it so far.A But, hey, it
would be all
A A too easy to remove.
A A Looking at the opening - it sure looks like the original intent
was to
A A put in a window.
A A I have sent an e-mail to Tom Tjaarda (attached) asking his
thoughts.
A A Hopefully he will respond.
A A In the interim, I put together a set of sensors so I could see
what I
A A could learn about conditions in the engine compartment just
inches in
A A front of the opening, to the right side of the dog-bone.A
A The attached
A A photo shows the instrument cluster shot from inside the car.
A A I'm measuring air velocity through the rear window (vane
anemometer)
A A Vacuum just in front of the window
A A Rotation of the a/c condenser fan (volt meter connected across
the
A A motor, which acts as a generator when the fan turns)
A A Two of the above are fairly straight forward.A The vacuum -
not so
A A much.
A A When one talks about a vacuum, one is usually talking about a
vacuum,
A A relative to ambient atmospheric pressure.A So, if a vacuum
gauge is
A A hooked up to your intake manifold, it reads the difference in
pressure
A A between the atmosphere where the gauge is sitting, and the
inside of
A A your manifold, where the hose from the gauge is connected.
A A So, what does one compare to in a moving car?A The interior of
the
A A car?A That is what one would get if one puts a vacuum gauge in
the cab
A A and routes the hose to the area in question.A But, what does
the
A A pressure (or vacuum) inside the car do with the car moving down
the
A A road.A Open the windows, your ears pop, and the pressure
changes.A Most
A A of us don't have an external air inlet (at least an intentional
one) to
A A the cab except for the windows.
A A My solution is to use a fairly sensitive pressure gauge (a
A A sphygmomanometer - gauge used to read blood pressure.A It
reads in
A A inches of mercury.A FYI, there are roughly 50 inches of
mercury per
A A psi).A I have connected the gauge with small-diameter plastic
tubing to
A A a 200 ml stainless sample bomb.A I wrapped the bomb in towels
and
A A placed in a cooler to minimize temperature changes.A See, the
pressure
A A in the bomb will change by roughly .03 psi (1.5 mm Hg) for each
1
A A degree F change in temperature.
A A I then pressured up the bomb and let it sit overnight to
stabilize.A It
A A ended up at 280 mm.A This is my "zero" at the then current
barometric
A A pressure.
A A One has to view the pressure gauge as a delta-pressure
device.A It
A A shows the difference in pressure between the bomb (high
pressure) and
A A the atmosphere around the gauge.A So, if the reading on the
gauge goes
A A up, the differential is increasing, which means the atmospheric
A A pressure is going down.A As in a wee bit of a vacuum around
the gauge.
A A Flip side, if the reading on the gauge goes down, well, there
is less
A A differential between the 280 mm Hg in the bomb and the
atmosphere
A A around the gauge, so the pressure is going up.
A A OK - that is complex.
A A While a gauge that can be read down to around 1 mm hg (0.02
psi) is
A A pretty sensitive, I suspect we are talking pretty minimal
vacuum
A A levels.A Preliminary testing suggested a reading of 272 mm Hg
at 80
A A mph.A The pressure around the gauge went up!
A A Huh.A A lot to learn here.
A A I also noted that the volt meter did not show any rotation of
the fan
A A on the a/c condenser.A Need to make sure the wiring is ok.A
But, note,
A A the meter reads in mV, and, in my earlier testing, it showed
voltage if
A A the fan turned at all.
A A The rubber for the new window shows up today, the window next
A A Wednesday.
A A My plan is to get a decent video and stills of the test
instruments at
A A several speeds.A Then, when the new window is installed, rerun
the
A A test.A I suspect the anemometer will still be valuable, since
I suspect
A A there will be a lot of turbulence in the air in the engine
compartment
A A even with the window in place.
A A Needless to say, having the window in place will complicate
putting the
A A deck-lid back in place.
A A Stephen Nelson
---------- Forwarded message ----------
From:A Stephen <[2]steve at snclocks.com>
To:A <[3]tjaarda at astranet.it>
Cc:A
Date:A Tue, 15 Mar 2016 10:01:30 -0700
Subject:A Pantera Rear Window
A A Good morning Tom.A Whilst I am pretty sure you have no clue
who I am,
A A being a member of POCA, I am aware of your contribution to the
A A Pantera.A And I thank you for what you designed.
A A Being fairly new to these cars (3 years) I am still learning a
lot.
A A One thing I have noted is the ability of my car to pick stuff
up off
A A the road when I am driving at speed.A I have found 1/4 inch
gravel
A A behind the inlet manifold and was amazed to see high water
marks on the
A A side of the rocker covers after a couple of hours driving in
the rain
A A at 70 mph.A Really quite neat actually, little wave pattern
down the
A A sides of the rocker covers.A Should have shot a picture.
A A None the less, I have queried the POCA forum about the absence
of glass
A A in the opening behind the top of the engine.A Folks indicated
no one
A A had ever tried installing glass, and some voiced concerns about
the
A A cars overheating if there was not lots of air flow past the
engine.
A A So, am writing to see if I can get your thoughts on the lack of
a
A A window in the deck lid and would appreciate any wisdom you can
impart.
A A Whilst I have done a number of upgrades to 5332, including
making the
A A engine a wee bit stronger, installing the best radiator and
fans that I
A A could identify, and getting the a/c so it keeps the car
comfortable, I
A A haven't really made any changes in the aerodynamics - like
wings or
A A spoilers or front air dams.A I suspect she would be a good
test mule
A A for such a window and plan to start my investigation by
figuring out
A A pressure (vacuum) levels above the engine at various speeds and
also
A A the direction of rotation and relative rpm of the a/c condenser
fan
A A (volt meter across the motor).A My thought is to then do the
same with
A A a window in place.
A A Any and all comments would be appreciated.
A A Stephen Nelson
A A [1]SNClocks.com
A A Click here to join one of our mailing lists [2]Contact Lists
A A Click here for our new [3]Hammered Dulcimers galleries
A A Click here for [4]my new blog on finding happiness in
retirement
References
A A 1. [4]http://www.snclocks.com/
A A 2.
[5]http://fs19.formsite.com/kagforms/form675003155/index.html
A A 3.
[6]http://www.snclocks.com/TheRestofourWorld/Hammered-Dulcimers/Abou
t-Steves-Dulcimers/19824807_4sHGgj#1558377542_LKmkrT7
A A 4. [7]http://www.perfectoldman.com/
_______________________________________________
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To manage your subscription (change email address, unsubscribe,
etc.) use the links above.
--
Michael L. Shortt
Savannah, Georgia
[10]www.michaelshortt.com
[11]michael at michaelshortt.com
912-232-9390
A
This email is protected by the Electronic Communications Privacy
Act, 18 U.S.C. Sec. 2510-2521, is confidential and may be legally
privileged.A If you are not the intended recipient, you are hereby
notified
that any retention, dissemination, distribution or copying of this
communication is strictly prohibited.A Please reply to the sender that
you
have received this message in error, then delete it.A Thank you
References
1. mailto:steve at snclocks.com
2. mailto:steve at snclocks.com
3. mailto:tjaarda at astranet.it
4. http://www.snclocks.com/
5. http://fs19.formsite.com/kagforms/form675003155/index.html
6. http://www.snclocks.com/TheRestofourWorld/Hammered-Dulcimers/About-Steves-Dulcimers/19824807_4sHGgj#1558377542_LKmkrT7
7. http://www.perfectoldman.com/
8. mailto:DeTomaso at poca.com
9. http://poca.com/mailman/listinfo/detomaso_poca.com
10. http://www.michaelshortt.com/
11. mailto:michael at michaelshortt.com
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