With a lowered car and stiffer suspension I find the stock 69 seats to be a little bouncy/springy over some of the roads around here. Mine have new repro cushions and covers and the springs were checked and repaired where necessary. I can handle the feeling of a firm ride but hate the unrestrained bouncing the stock seats seem to have. I'm after something more like the feeling of stock 2001 seats.

After toying with the idea of messing with the suspension I decided it might be worth the time to mess with the seats a bit. I've ordered some closed cell foam and minicel foam pads. I think I will try to shape them to fit under the seat and fab/attach a "bottom" of sorts to keep the foam up under the seat and not allow it to hang down to the floor.

The foam is a medium firmness used for seat cushions and is supposed to have excellent shock absorbtion properties.

Any one else out there modify their stock seats somehow to resolve a similar issue?

I had mine all redone as well and the springs were repaired. They are really bouncy too. I wish I would have installed new springs but the interior guy talked me out of it.
Jack

The spring's should have been replaced,after 37+ years they are weak.They might feel ok when you put pressure on them with your hand's,but when you put your body weight on them you find out real fast just how weak they are.

There was a thread here a couple of yrs ago about how to use a high desity foam under the springs to supplement the old springs. I know that I bookmarked it and put in one for the many folders that I have created. My seats are bouncy too and I saved the link but just have to find it. The "bottom" as I recall was cut out of plywood and fashioned to rest on the seat frame to keep the foam from view. Will post if I have any luck.