Silver72

Can someone explain to me what "Astro Ventilation" is and how it works?

Thanks,

Steve

hunt4cleanair

Sure...Astro Ventilation was introduced in 1968 as a flow through of fresh air symbolized with a single pane of side glass, eliminating the side vent window that had characterized automotive manufacturing, including the first two Corvette generations. In 1969, the side glass sported white script letters at the front end of the window used into the 1975 model year. The transition from Astro Ventilation glass began in 1975 so some early models are equipped with the Astro glass until the supply was exhausted…same with convertible glass. It’s also reported that late 1974 built cars were equipped with 1975 glass and therefore may not have the Astro script.

Astro Ventilation incorporated vents at the front end of the cabin with vents at the rear deck just behind the rear window. Air flows from the cowl, collecting in the plenum, flowing through both dash vents (ventilation *****) and the kick panel vents, flowing through the cabin, moving through the cabin out through the rear deck vents.

Hope this helps!

Gordonm

I just redid mine and you can see a picture of the vents in my other thread about Redid my rear vents. I will post a picture of the whole setup once I get it back in the car.

RHD '68 L89

68's had the Astro Ventilation script on the glass as well

Eddie 70

Just one more thing to add. The astrovents will stay open anytime the temperature controls are in the minimum position. Dial up any heat and the astrovent doors will go closed, obviously to save heat in the car.

RHD '68 L89

Another 68 only thing-
There were only flaps in the rear to stop water and reverse air pressure from entering the cabin.
In 69 the vacuum motor was added to stop the loss of hot air, Like we need to stop hot air escaping

hunt4cleanair

So what do you do to activate the vacuum motor?

StickShiftCorvette

Anytime the temp control is above full cold, the exhaust door closes. BTW, only non-AC cars have Astro Ventilation.

grybdn

my 71 had "air" and "Astro ventallation" windows.

BBShark

I have a 68 (completely apart) and I have been debating about restoring the old passive "flap" system, converting to later active, vacuum operator door or closing off. Any 68 owners have a recommendation?

Tom73

The logo was on the windows of all, but only non-A/C cars had functioning astro-ventalation.

tom...

carl a

my 73 came from the factory with a/c and has astro vent scribed on the windows

RHD '68 L89

You would have to change the controls to a later unit as well. I say leave it alone, can't see it making that much difference unless you are driving it in the snow and need the sealing. I think as much airflow as possible is a good thing.

René K.

I was always wondering what this "Astro Ventilation" was supposed to be. However... my 1972 Coupe (with air condition) has the script on the side glass... but the rear deck vents do not have any flaps nor vacuum operated mechanism... they just have the usual drain hoses leading into the wheel well.

Does anyone have pictures of that area from inside the vehicle showing all the mechanics!?!

Thanks!!!

Cheers...
René

Alan 71

Hi Rene,
The Astro Ventilation system was developed when side 'vent' windows were done away with for the 68 model year. The idea was to have fresh air enter at the cowl and flow through the interior to exit through these vents. The vents closed automatically when the temperature control was turned to 'H'eat.
Here's part of the 'astro' system on a 71 coupe. It's the left side right behind the driver's side seat.
Regards,
Alan

You can see the vacuum actuator that opens and closes the door on the right and part of one of the metal doors on the left.


The drain hose for the plenum that the door open and closed into.

René K.

Hi Alan,

thanks so much for your explanation and the pictures! That helps a lot!

However, I have checked my car... and there is nothing (no vacuum actuator... no vacuum hoses... no flaps ... Is it possible, that 1972 Cars with air condition do not have this feature at all / anymore... probably deleted like the removable rear window for 1973?

Cheers...
René

oldgto

Only cars without AC have the flapper doors

Alan 71

Hi Rene,
Here's a picture from a prior post showing an a/c convertible with the block- off plate in place.
The convertible system was in a slightly different position because of the differences between coupe and convertible body configurations.
Regards,
Alan

René K.

Hey guys...

thanks a lot for your responses, explanation and pictures.

Now it is clear to me... AC has no vent flaps but a block-off plate... that is how my car looks like! So everything is as supposed.

Cheers...
René

CA-Legal-Vette

Did the convertibles with AC not get it? Mine does not have any of these mechanisms.

Had to chuckle when I saw this. I had mine most of a year before I noticed that the heat didn't work