I noticed the same thing on my old 91 Pont sunbird.

I just thought it was normal

My Lebarons have all had a head liner covering the inside so I con't tell what it's doing.

Replacing the top won't fix it.. Finding & fixing all the places air gets into the car will fix it, it is being pressurized... To be honest it's very typical of vintage convertibles..

There are several factors, including air flow and pressure. A tighter top will raise less, but they will all still raise some.

The center of the roof has a low pressure area in relation to the atmospheric pressure in the interior. The larger the top surface area and the steaper the windshield the more pronounced the low pressure.

I just crack the rear windows about an inch which equalizes the pressure and allows the top to rest on the bows.

Carmak
Riverside, Iowa

did you ever see a convertable go down the quarter mile? about halfway down it starts to look like jiffy pop popcorn poping.

who drives a convertible with the top up?