[PB]

I recently purchased a 72 convertible. It has a great working factory AC. When I run it and I am driving down the interstate, the cabin pressure really stretches the conv. top to the limit. It is very taught and has already pulled away from the center post seam a bit. When I crack a window, the pressure is relieved a bit and the top isn't as taught.
Is there a way to relieve the pressure without opening a window when driving at highway speeds? And, what glue is strong enough to keep that center seam attached to the top and the center bar? Thanks for any help, Pat

[PB]

I recently purchased a 72 convertible. It has a great working factory AC. When I run it and I am driving down the interstate, the cabin pressure really stretches the conv. top to the limit. It is very taught and has already pulled away from the center post seam a bit. When I crack a window, the pressure is relieved a bit and the top isn't as taught.
Is there a way to relieve the pressure without opening a window when driving at highway speeds? And, what glue is strong enough to keep that center seam attached to the top and the center bar? Thanks for any help, Pat

[gtoformula]

Are the vents in the quarter panel part of the door jamb blocked? Have you sealed the trunk divider wall too tightly? Air flow is designed to from the interior, through the trunk and out the door jamb vents. If it is plugged or the air flow is restricted it can't vent properly causing interior air pressure.

[PB]

Well, that very well seems to be my problem here. Seems there is no vents in the door jambs at all. Very strange, the guy that restored it must have pulled them out for some reason. Looks like there never was vents there in the first place. I may have to cut holes and install the vents. Thanks a lot for your input...Pat

[gtoformula]

Let's not get too hasty here regarding cutting holes in your car. My car is a hardtop so maybe the convertibles don't have the same vent in the door jamb. We have two restored 1970 convertibles in our local GTOAA chapter. I'll email those guys and see what they have to say.

[milind]

My 1970 convertibles have no vent in the door jamb

[gtoformula]

Oops. I checked with one of my buddies that has a convertible 1970. He says that it doesn't have door jamb vents. Sorry for the confusion and good luck with your issue.

[PB]

Thanks for checking on that. I haven't done any cutting, but that seems strange to me that convertibles would not have the vents. I have a 69 hardtop that dosn't have vents either, so I wonder what years they first were installed. Maybe some other people have some insight on the air pressure issue....anyone? Pat

[Andre]

I don't know if this helps or clouds things up, but the NOS 70-72 quarter panels do NOT come with the door jamb vent opened up. You have to cut it open yourself.

I think the 72 cars have another system behind the back seat.

[70 Dream]

The door jambs on my 70 convertible are not vented.

[satman]

My 71 does not have the vent. Funny thing, I have seen Chevelle & Skylark Convertible with them, so it must be a Pontiac thing. I am really impressed that your convertible has such a great seal. Mine must leak like a sieve, I do not have this problem. Sorry I can’t help.

[engineer]

run the AC on normal or bilevel, not max to reduce the air pressure.