slippery shape (1976 Aerovette -- anyone know Cd?)

[aerohead]

Originally Posted by royanddoreen

.325!!! with that shape. It looks to have the best boatail i ever saw, must be a mistake. Any other cars with a tail shape like this one? Guess i must start scearching to see what i can come up with.

This is probably one of those "just because it looks low drag doesn't mean it's low drag."
Hucho comments on 'pseudo-Jaray' 'fastbacks' which have too steep of a roofline and suffer not only premature separation,but also horrific longitudinal vortices,adding up to high overall drag.
The Corvette of '73 was around Cd 0.5,and when Datsun (Nissan) came out with their 240-Z it was over Cd 0.5.Ferraris,Maserattis,and Lamborghinis didn't fair much better.
And we hadn't had the Arab oil embargo yet,or any full-scale wind tunnels except Lockheed Marietta,so it was mostly about styling.

[RiderofBikes]

hell, the 2011 fiesta has Cd of .33, but id love to have that Vette!!! Just for styling or not it still goes faster than the ford anyday, and looks so simplistic on the inside(maybe full HD display?). If i could, id love to mimic it in almost every way, but redo the "fastback" portion of it and elongate it to match template, smoothy wheel covers, and give it a smooth underbelly(assuming it doesn't have one for 70's tech), give it a decant little 6cyl with a double overdrive... who knows whats possible.

Curious of the influence, if by adding a small lip tail section would of had on it?!

[Sven7]

Let me poke around at the library and see what I can find. 0.325 sounds about right for something that's shoving a bunch of air under the car though. Who knows- there might be some wind tunnel pics or something.

Oh yeah, and that rear slope is probably pulling all the air down instead of letting it move at its own pace. Can't imagine it would be fun to drive at 120mph.

[kach22i]

I think allowing air at the nose under the car is alright as long as you manage the air-flow underneath with a smooth belly pan or something.

Many forum comments about lower is not better in certain cases.

EDIT: found this scale model picture.

Aerovette - Autos - Modeling Subjects - Finescale Modeler Community


The real thing (1973 not 1976) is at the GM Heritage Museum, can someone make it over there and snap a picture of the belly?

1973 Chevrolet Aerovette Concept Images, Information and History (Experimental, Gull-Wing) | Conceptcarz.com

The Aerovette was designed wîth the aid of wind tunnel testing for low drag without excessive aerodynamic lift while maintaining Únited States bumper height standards. ( posted on conceptcarz.com)

The GM Heritage Center serves as a showplace for the vehicles of the GM Heritage Collection, and as the home of the Heritage and Media Archive. Located in an 81,000 square foot facility in Sterling Heights, Michigan, the Center has approximately 200 vehicles on display, while the Archive houses 15,000 linear feet of shelving containing significant documents, manuals, brochures, and artifacts documenting GM's rich history of innovation.

About | GM Heritage Center
Conference and Event Planning
Though not open to the public for individual visits, The GM Heritage Center can be reserved for group tours, conferences, meetings and special events.

Guess I'll have to wait for a special event when it's open to the public.

[Grant-53]

The Cd for the Aerovette is correct. If you are interested in the shape, there were 1/24 scale paper model forms published in Motor Trend during the early 1970's. I had prints made from our local library microfiche. The Citation IV was the better aero protype.

[royanddoreen]

Originally Posted by aerohead

This is probably one of those "just because it looks low drag doesn't mean it's low drag."
Hucho comments on 'pseudo-Jaray' 'fastbacks' which have too steep of a roofline and suffer not only premature separation,but also horrific longitudinal vortices,adding up to high overall drag.
The Corvette of '73 was around Cd 0.5,and when Datsun (Nissan) came out with their 240-Z it was over Cd 0.5.Ferraris,Maserattis,and Lamborghinis didn't fair much better.
And we hadn't had the Arab oil embargo yet,or any full-scale wind tunnels except Lockheed Marietta,so it was mostly about styling.

So that roof line if a little steep is worst than like a prius less steep but cuts off square like most all cars?

[Sven7]

George, I'm planning to head up there soon, so hopefully I'll remember. Maybe there's some kind of employee field trip

It's not that letting air under the car is necessarily bad- it's that the nose is so high that it is compressing air before it goes under the car. That's bad for aero and bad for stability.

[kach22i]

Originally Posted by Sven7

George, I'm planning to head up there soon, so hopefully I'll remember. Maybe there's some kind of employee field trip

Cool, wish you luck.

[royanddoreen]

This is the aero shape car i was looking for!!!file:///C:/Documents%20and%20Settings/WinXP/My%20Documents/Downloads/2013%20Volkswagen%20XL1.htm!

[some_other_dave]

Sorry, that's a local file on your computer. To share it with us, you need to either find it online and share the link, or find some place to upload it to and then share the link with us.

Or if it's a picture, using the "go advanced" button or the "post reply" button (i.e., not the "post quick reply" button) and scroll down to "manage attachments" so you can upload the picture that way.

-soD