I have a 1980 and the hood latches located near the windshield are acting up lately. I have seen this on other late C3s as well. One or both of the sides will sit up about a quarter inch higher and feel loose. When I drop close my hood from the windshield center from about 4" high with slight downward force, both sides would normally latch tight. Now sometimes/ most of the time one or both will latch but not tight. When I press the corner it will move up and down alittle but not latch any tighter. On these later C3s there does not seem to be any adjustment that I know of except shims, am I missing something? I don't want to slam the hood? Isn't the latch either made or not made? It seems like it is not clicking all the way but yet it is still latched??

If the '80 is like the '71 or '75, you can loosen a large keeper nut under the spring and screw down the latches with a large flat blade screwdriver.  I know Joel must have a pic of this.

Well, no...actually I don't.
The later cars have different latch systems, anyway. It should still be adjustable, tho. I have a problem with the '74 that I finally gave up on, in that the driver side latch will not hold, and it will pop up after a few miles of driving. I've adjusted the latch and the pin so many times I can't remember. I will eventually replace the latch.
FLA VETTE, do you have the rubber bumpers for the cowl, that sit close to the latch area? If the hood is latching properly, and not coming open, then I would look into whether or not the rubber support/bumpers are there, and adjusted correctly, to get rid of the excessive free play, with the hood closed.
I bet Mike(mkapp)will have a photo, and info on adjusting the later car hoods.

After I woke up, I remembered, the later cars have way different hood latch mechanisms.
The upper "bar" parts on the hood are adjustable down, but not up. Nor are the ones on the cowl adjustable to make the hood fit farther down, or to take up any excessive free-play in the hood when closed. You have to have the rubber bumpers adjusted to do that. I'll see if I can find more info on this...

Also, make sure the release cable is fully retracting when you open the hood. If it doesn't go back to "closed" position, the hood may not latch on one, or either side.

Seems strange that they didn't build it with an adjustment. My hood is very level everywhere when latched properly on both ends. When it sits up that quarter inch I think the latch has closed just not all the way, it may also be that it feels latched but is not at all and only held by the one end.  I am going to play with it some more this weekend.

May sound brutal but when I lower my hood(s) I drop it the last 15" or so. Usually latch OK. Never any indication of any damage to it doing this. I remember my 69 GTO, closing the hood "carefully" and noticing the dent from pushing it down. Started gently slamming it after noticing those dents. Been a slammer ever since!  Mike

I'm wid you, Mike! I drop mine down from probably 15"-20", too. It always shuts fine. The only side effect on mine is where the bumper on the driver's side is. It sits so low that the bottom of the screw part has gouged into the 'glass on the cowl/firewall area directly under it. It's not bad, and most people never notice it. It was like that when I got the car, so I don't give it much thought anymore.Adams' Apple2006-11-03 21:10:22

OK, got some time to look at it again. The latch is either made or not, no partial latching. I did replace my spring rubber feet a couple months ago when I had the springs out for painting. Noticed this weekend the drivers side spring was catching a little when I pressed down by hand. Rotated the spring and now she seems to latch good both ends. Problem fixed for now...... I think. Well, I only tested a couple times with success, will see if it holds up over time. I have lowered my drop slam height over the last few months cause my air cleaner is now so close to the hood and I am afraid of hitting during the slam.