As I'm working through the car and getting everything prepped for paint, I've been purposely ignoring the rear trunk lid. There is a lot of flex in the middle of the lid skin that oil cans / tin cans when you push hard enough on it. On the underside, there is no webbing or support for a fairly large section of the trunk lid skin.

Is this amount of flex normal or do I need to shrink the skin? I'm afraid that I will make it far worse by trying to shrink it since it is such a large area.

Here is a quick video showing the flex: Link to YoutTube Video.

Mine is the same way, one thing to remember.................. don't let anyone sit on the back edge of the rear trunk or close your rear trunk higher then the main inner supports of the lid. This happened to me, I believe at the repair shop. I didn't notice for some time later. I was able to pop most of it out except a small cup above the inner support. Mike Kelly

Basically, don’t let anyone touch your car. The metal is so thin. Years (and years) ago, my girlfriend at the time, closed the passenger door with her hip because her hands were full. She was a little wisp of a girl and still caved in the door (early car, no side impact beam).
911 guys think you are supposed to close the front trunk by pushing down on the Porsche emblem. Wrong! That’s why 911’s all have a shallow spot under the emblem.

At least it pops back up. some oilcanning will stay down and you have to push it back up from the back.

So, is the general consensus to leave as-is and not worry about trying to shrink it?

If it’s the right curvature now, leave it as-is. Maybe at one time the skin was pushed down hard enough to bend the ribs. If that’s the case, you might just want to live with it if the trunk still looks good. Sometimes perfection is the enemy of good.

It's mostly normal. I've had a few of those and they all do it. A little flimsy I'd say but as long as you don't mess with it, it's fine.

Hey Guys,
The last 914 I did, the deck lid oil caned
So bad it was difficult to block sand primer
With out the metal popping down.
After looking at the support braces on the
Underside I noticed they were not actually
Touching in back part of the lid. I turned
The lid up side down on flat surface, hammered
Edges of support down with dolly. This
Brought the support real close. I then cut
Strips of Dynamat Insulation, placed between brace
And inter skin(not to be seen) It greatly improved,
And blocking was not a problem.
Hope this helps someone
Bruce

I essentially did the same thing, turned the lid upside down and got the braces to fit a closely as possible to the skin and then filled the gap at several points along the braces with panel bonding adhesive and then turned the lid back upright and made sure the skin was not "oil canned" down. Once the adhesive was cured the skin was rock solid and easy to sand without it popping in and out.

I just dealt with this on my project,
Re-do the adhesive/bonding goop between the skin and the ribs.

So upon further review, one of my ribs is definitely pushed down as if something heavy was set on the lid at some point. That probably explains the oilcanning.

For those who talked about bending their supports back and re-adhering... What is the best way to bend these back in shape without compromising the skin? Heat? Cut & Weld? Lots of banging? All of the above?

Hey Aggiezia,
I’ll try to send pix to show procedures
I use body tool, a flat bar would also work.
No need to heat.

Bruce