Most of us humans get saggy after several decades, but my engine lid will not stay in the upright position. All looks ok, I can't imagine the torsion bars lose their power?
TIA

Look at hinges - probably has broken spot welds and separating from rear bulkhead.

That is the usual cause.

These
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Check the "L" brackets to which the lid bolts. Dollars to donuts one or both are cracked and pulling away from the fire wall. Pretty common.

I think the torsion bars can lose their strength over time. If the hinge brackets are okay, try swapping the torsion bars so that they bend in the opposite direction. This worked for me. For extended periods I leave the engine lid open (covered in garage) so it's under less tension. I also leave the targa top latches undone (rears hooked) so the top seals are not compressed.

Sagging is usually not the problem, it’s the hairy and closer to the the ground that bothers me

thanks, the mounting brackets are in great condition and 90 degrees to the firewall with no visible cracks. I was hoping the torsion bars did not lose their ability to resist twisting, but apparently they do. I will switch them and hope it cures the sagging/drooping

If they are like the bales on the valve covers, you can put in a vice and try bending back some tension. You have nothing to loose.

thanks for the tip, I am often a CSOP

Hey why spend it if you don't have to. You know I'll be making more parts you need soon

If the tortion bars are sagging yourcould increasethe tension by putting a rubber block under the end ofteach bar.