NACA HOODS FOR '71 TO '73 MUSTANGS. CORRECT OR INCORRECT!

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1973 Mustang Convertible
Hi to all,

Stumbled across this new article put up in the daily Hagerty Media outlet. It's a write up regarding the 10 coolest cars with NACA hoods. Going through the article, i noticed that our 1,2,3 Mustangs didn't get a mention at all in the ten listed. The post written by Scott Oldham, goes to the trouble of first giving a history background on NASA ducts, and what constitutes or what exactly is the definition of a NACA duct.

According to the article, and the public article feedback, our Mustangs don't rate as a true NACA ducting system, as our hoods have a raised profile area directly above the duct itself. If this is the case, then how come our hoods have always been called NACA hoods by just about everybody in or out of the motoring world forever and a day.:confused:

So what's going on here? Have the Hagerty guys got it wrong, or technically, they are right? The comments or reply section is worth reading as well.

And lastly, could someone explain to me how the word NACA became or ended up being called NASA. Calling our hoods NASA - correct or incorrect?
Reading the article, and going into the history, i would have thought that both words are correct. However, there seems to be confusion around this as well.

Link ........................................

https://www.hagerty.com/media/desig...4fd641e1fbc2b48417387a002882e9ed543509d2b1eca
Greg.:unsure:
 
Last edited:
"Naca", stands for National Advisory Commitee for Aeronautics ( NACA ), which, in 1958, was changed to National Aeronautics and Space Administration (NASA), which continues today. The design was drawn up to induce airflow without having an airscoop protruding into the airstream, which would also produce drag, and interrupt airflow across the surface.
 
"Naca", stands for National Advisory Commitee for Aeronautics ( NACA ), which, in 1958, was changed to National Aeronautics and Space Administration (NASA), which continues today. The design was drawn up to induce airflow without having an airscoop protruding into the airstream, which would also produce drag.
Hi Spike,

OK, so in your opinion, would both words used to describe our hood be technically correct? (NACA/NASA).

Greg:)
 
The style of ducts were invented when the agency was called NACA, therefore "NACA" is correct - on just about any other application they're still called "NACA Ducts." Just because they changed the name of the agency later, doesn't make them "NASA" hoods... but so many years of referring to it wrongly can't seem to be erased. As well, Ford themselves referred to them as NASA hoods, so I guess they're technically "NASA Hoods," even though Ford was wrong when they coined the term. And here we are 50+ years later still debating which is correct. ;)
 
According to the article, and the public article feedback, our Mustangs don't rate as a true NACA ducting system, as our hoods have a raised profile area directly above the duct itself. If this is the case, then how come our hoods have always been called NACA hoods by just about everybody in or out of the motoring world forever and a day.:confused:

One word - marketing.

Space and anything associated with it was hot in the late 60s.
 
One word - marketing.

Space and anything associated with it was hot in the late 60s.
Best concise response yet in this thread. "Marketing."

Now, for my expanded thoughts on this particular design angle... heh heh...

I was born in 1954, and I recall as a kid all the hype surrounding a lot kinds of products and service as being affiliated somehow with the "jet age" or "space age." Much of it made no sense other than the sellers trying to call upon the powerful ghosts of whatever era they were alluding to being part of. I see a similar thing in politics in the past few decades, where candidates who want to paint themselves as being conservative often call upon the "Ghost Of Reagan" in an effort to enshroud themselves with his flavor of "the good old days" (which weren't all that good). I see Ford having taken the NACA label, and realizing most folks would not recognize what NACA was, whereas everyone knew about NASA - likely due as much to the impact of the TV show, "I dream of Jeannie," as anything else. NASA was held in great esteem. Hence the likely reason Ford called the hood a NASA hood. And how could anyone refute that label being associated with such a mean, cool looking hood with an obviously highly aerodynamic look?!? That hood and twin intake duct look all but ensured the 71-73 Mustangs so equipped would be as fast as the high speed aircraft they were designed to emulate in performance if nothing else.

For me, I could not give a rat's set of tail feathers what the hood design is called. It is a really cool design, whether it really does any real good or not. In my case, for our 73 Mach 1, our NACA/NASA hood had the inlet duct blocked, so it was a non function but good looking design. I decided to get a Ram Air kit from NPD when I ordered a replacement hood (rusty areas in a few small areas when we bought it about 6 years ago). I had no illusions re: the added performance some/many folks would expect to see as Ram Air <> Forced Induction.

As it turns out the lower part of the air cleaner housing that came with the kit would not sit on top of our Holley 750 CFM Vacuum Secondary carb. Of course, I found this out after I had installed the plenum on the underside of the hood, and hd the vacuum lines run to the two vacuum motors that opened and closed the inlet flaps (I had by then also removed the plastic locks from the inlet ducting). So, I ended up doing what I could to help preserve the one benefit I was after, while shedding the rest. I ended up keeping the 360 degree open air filter and housing in place, removed the plenum and vacuum motor vacuum lines, leaving the inlet ducts in a wide open position full time. The idea was to just let cool air come into the underhood area near the carburetor air intake and the rest of the underhood area. That was where any benefit would be coming from anyway, a cooler air temp for the carb, and maybe some heat quenching for the underhood temperature in general.

Even if the underhood air pressure at seed kept the inlet ducts from pulling and directing cool air into the engine compartment, it still looked really cool, especially with both inlets actually being wide open all the time. At least they gave the illusion of doing "something" because clearly anyone looking into the ducts would see the engine under the hood. That was worth some goody points if nothing else.

Then comes the other cool aspect of our NACA/NASA scoops. When we did the restoration on the 73 Mach 1 we decided to not use a tradition "RAM AIR" or "351 RAM AIR" set of decals for the Call Out characters. Inspired by the way the side stripe tape on our 69 Shelby GT500 was used to let the underlying Candyapple Red paint make up its "GT500" Call Out characters, I found a "351 RAM AIR" Callout in a paint stencil. The resultant underlying Sunset Orange metallic beneath the Hot Rod Black Matte schema very nicely quite boldly shouts out the fact the Mustang is powered by a 351 RAM AIR equipped engine. Personally, I think the back paint mask over underlying color paint really looks good. And when combined with the "really open" venting of the inlet ducts the "cool factor" definitely makes an impact. Never mind the allegedly incoming cool air may not really do anything all that effective. It definitely looks cool, and for me that is all part of what makes these vintage Mustangs so awesome. They flat out look cool, and their coolness can be built upon to some reasonable degree like we did on our Mach 1.

https://youtu.be/_Fl0B-qmlLI
 

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Hi to all,

Stumbled across this new article put up in the daily Hagerty Media outlet. It's a write up regarding the 10 coolest cars with NACA hoods. Going through the article, i noticed that our 1,2,3 Mustangs didn't get a mention at all in the ten listed. The post written by Scott Oldham, goes to the trouble of first giving a history background on NASA ducts, and what constitutes or what exactly is the definition of a NACA duct.

According to the article, and the public article feedback, our Mustangs don't rate as a true NACA ducting system, as our hoods have a raised profile area directly above the duct itself. If this is the case, then how come our hoods have always been called NACA hoods by just about everybody in or out of the motoring world forever and a day.:confused:

So what's going on here? Have the Hagerty guys got it wrong, or technically, they are right? The comments or reply section is worth reading as well.

And lastly, could someone explain to me how the word NACA became or ended up being called NASA. Calling our hoods NASA - correct or incorrect?
Reading the article, and going into the history, i would have thought that both words are correct. However, there seems to be confusion around this as well.

Link ........................................

https://www.hagerty.com/media/desig...4fd641e1fbc2b48417387a002882e9ed543509d2b1eca
Greg.:unsure:
You might also mention that the only cool car on the list is the 69-70 Shelby Mustang and the Dodge Viper. The other cars in company are a 1973 GTO???? A stinkin French car????? Cars I never heard of? Dont get worked up over all of this as this guy is obviously insane!
 
Best concise response yet in this thread. "Marketing."

Now, for my expanded thoughts on this particular design angle... heh heh...

I was born in 1954, and I recall as a kid all the hype surrounding a lot kinds of products and service as being affiliated somehow with the "jet age" or "space age." Much of it made no sense other than the sellers trying to call upon the powerful ghosts of whatever era they were alluding to being part of. I see a similar thing in politics in the past few decades, where candidates who want to paint themselves as being conservative often call upon the "Ghost Of Reagan" in an effort to enshroud themselves with his flavor of "the good old days" (which weren't all that good). I see Ford having taken the NACA label, and realizing most folks would not recognize what NACA was, whereas everyone knew about NASA - likely due as much to the impact of the TV show, "I dream of Jeannie," as anything else. NASA was held in great esteem. Hence the likely reason Ford called the hood a NASA hood. And how could anyone refute that label being associated with such a mean, cool looking hood with an obviously highly aerodynamic look?!? That hood and twin intake duct look all but ensured the 71-73 Mustangs so equipped would be as fast as the high speed aircraft they were designed to emulate in performance if nothing else.

For me, I could not give a rat's set of tail feathers what the hood design is called. It is a really cool design, whether it really does any real good or not. In my case, for our 73 Mach 1, our NACA/NASA hood had the inlet duct blocked, so it was a non function but good looking design. I decided to get a Ram Air kit from NPD when I ordered a replacement hood (rusty areas in a few small areas when we bought it about 6 years ago). I had no illusions re: the added performance some/many folks would expect to see as Ram Air <> Forced Induction.

As it turns out the lower part of the air cleaner housing that came with the kit would not sit on top of our Holley 750 CFM Vacuum Secondary carb. Of course, I found this out after I had installed the plenum on the underside of the hood, and hd the vacuum lines run to the two vacuum motors that opened and closed the inlet flaps (I had by then also removed the plastic locks from the inlet ducting). So, I ended up doing what I could to help preserve the one benefit I was after, while shedding the rest. I ended up keeping the 360 degree open air filter and housing in place, removed the plenum and vacuum motor vacuum lines, leaving the inlet ducts in a wide open position full time. The idea was to just let cool air come into the underhood area near the carburetor air intake and the rest of the underhood area. That was where any benefit would be coming from anyway, a cooler air temp for the carb, and maybe some heat quenching for the underhood temperature in general.

Even if the underhood air pressure at seed kept the inlet ducts from pulling and directing cool air into the engine compartment, it still looked really cool, especially with both inlets actually being wide open all the time. At least they gave the illusion of doing "something" because clearly anyone looking into the ducts would see the engine under the hood. That was worth some goody points if nothing else.

Then comes the other cool aspect of our NACA/NASA scoops. When we did the restoration on the 73 Mach 1 we decided to not use a tradition "RAM AIR" or "351 RAM AIR" set of decals for the Call Out characters. Inspired by the way the side stripe tape on our 69 Shelby GT500 was used to let the underlying Candyapple Red paint make up its "GT500" Call Out characters, I found a "351 RAM AIR" Callout in a paint stencil. The resultant underlying Sunset Orange metallic beneath the Hot Rod Black Matte schema very nicely quite boldly shouts out the fact the Mustang is powered by a 351 RAM AIR equipped engine. Personally, I think the back paint mask over underlying color paint really looks good. And when combined with the "really open" venting of the inlet ducts the "cool factor" definitely makes an impact. Never mind the allegedly incoming cool air may not really do anything all that effective. It definitely looks cool, and for me that is all part of what makes these vintage Mustangs so awesome. They flat out look cool, and their coolness can be built upon to some reasonable degree like we did on our Mach 1.

https://youtu.be/_Fl0B-qmlLI
 
You might also mention that the only cool car on the list is the 69-70 Shelby Mustang and the Dodge Viper. The other cars in company are a 1973 GTO???? A stinkin French car????? Cars I never heard of? Dont get worked up over all of this as this guy is obviously insane!
Exactly! When it comes down to it, they’re just filling a magazine with words to sell products. Maybe it’s just the inner child in me, but I only read it for the pictures.
 
Wow! I had no idea I'd stir up so much convo. I'm the Nick that posted the comment. Although, I don't appreciate Brian's response in his attempt to shame us 71-73 owners.2023-04-20_07-50-17.jpg
 
Wow! I had no idea I'd stir up so much convo. I'm the Nick that posted the comment. Although, I don't appreciate Brian's response in his attempt to shame us 71-73 owners.View attachment 75849
I think the comments are both wrong.

The very first car in the list is a 69-70 shelby mustang.
Point 1 - Look at the shelby. The hood is raised over those ducts. Derp. there goes that theory.
Point 2 - The list is chronological. they had literally just listed 69-70 mustangs. If they then listed 71-73 mustangs, it would make the list more boring and repetitive.

The reason they left 71-73 mustangs off is purely that. Its a website with a top-10 list. They want to keep it interesting for the average reader, to try and draw in more clicks, and more ad revenue. Having the very first 2 items on the list be so similar makes for a less interesting list.
 
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