I'm bored....I want to drive my car but this winter snow just won't leave (ya and its only the 1st day of winter....). So in the mean time I'm boning up on my 72. So what is the function of those rear vents on the back deck, behind the rear glass? I see in my manual that they are vacuum operated. When do they open and why? I can then add them to my list of things to check for proper operation.

Thanks again!
Dave

Astroventilation exhaust ports.  If you move the heater control to HOT, the air exhaust doors close.  --from my '69 owner's manual

Nifty! I'll give a test....thanks!

Unless your car is air conditioned in which case they don't do anything at all...they're blocked off.

Thats kinda weird. What, if you have AC you will never use your heater? Or maybe there is another vent in the AC system? I don't have AC. I also have to figure out why when I turn the heat on it dumps from the dash area over the center gauge cluster. I wonder if I'm missing some vent ducting.....

With AC, the fan runs on low all the time...even if you shut it off. It pulls in fresh air that way or so GM thought. I find putting the windows down much more effective.

Not sure why you're getting heat above the gauges. You shouldn't have any vents in the middle; only a block off plate that says "Corvette". The windshield defrost ducting runs up behind the gauges though.

i bet the defrost duct is missing or not lined up. I'm finding all sorts of goofy assembly issues from the so called Corvette specialists who assembled the car post frame off. I need to figure out why the "rebuilt" steering column flops around. The tilt joint does not positive lock the column. It does not jump out of it selected "tooth" but its wobbly...maybe half an inch up at the wheel. I think the tilt locks were installed upside down or backwards or something. The thing is....it also moves from side to side some. And the turn signals don't work, nor the brake lights. And its all new parts. I'm thinking I'll find that the harness was left unplugged. Oh ya, the back up cable end from the trans linkage is not attached either. What does that do? Light up a reverse warning light on your dash? I'll have to check backup lights...but I think those trip off a switch on the trans right? Fun and games.....

The cable from the trans to the column keeps you from removing the key unless the trans is in Reverse. The back-up lights do work off of a switch mounted to the side of the trans, with a small wire linkage from the switch to the reverse shift linkage.

Is the idea that you should put the car in reverse to park vs. 2nd like I do in all my other manual shift cars? I bet all of this is addressed in the uses manual I don't have. Are there any PDF's of this online? I couldn't find one.
Thanks,
Dave