KHM seat pads vs. other brands?

[Doug McAllister]

Hi
I'm early in the restoration process on my 1969 280SL, and am doing a partial interior re-do. I have a nearly 100% original car with 85K miles. Always garaged, not driven in about 15 years, and only some sun damage. Literally driven by a little old lady to the store (my mother). My father bought it new at the factory (living in Germany at the time) when I was 15 and I got my drivers license in this car in 1970. It has been passed on to me. I'm starting with interior/windows/doors, then will be suspension, followed by engine and finally paint over next two years or so. I have spent may hours reading on this excellent forum and am very thankful for all of you fellow enthusiasts.
I decided to go with World leather seat covers (original MBtex has a rip by the seat lever, and sun damaged piping) and World tex door panels (dark spots on upper edge due to sun damage). My thinking is keep original except I want to sit on leather.
They are ordered after much reading on this site - not received yet ( concerned about color/texture match - will post pics later) Cognac interior.
My question revolves around the VERY expensive seat pads (~$325 each piece) on GAHH or GAT vs. the more reasonable KHM (in Germany), rubberized hair/foam compound pads (~$125 each piece). These will be a little more after shipping, but it does include German VAT.
https://www.cabrio.de/khm/en/padding-panels-backseat/panels-and-seat-paddings
Does anyone have experience with these? Do they hold up over time? I am planning to do the noodle upgrade as I do them.
Thanks
Doug

[stickandrudderman]

The KHM pads are very good and the noodle upgrade should not be necessary if the springs are in good order. There is a company in Germany that makes new seat springs but I haven't tried them they advertise on eBay.

[zoegrlh]

You I would go with the original OSN MB pads. I got mine several years ago from MB, cost a little more but best quality. However someone has told me recently that MB Classic Center has no stock available corrently. As we all know when MB depletes its classic parts inventory it will manufacture new stock. Does anyone know if in fact MB is out of stock for these pads?
Bob

[mdsalemi]

...and the noodle upgrade should not be necessary if the springs are in good order...

The seat springs are made of what is called "loop upholstery springs" and this materiel can be purchased in long coils (quite ironically, one supplier sells it in 113 foot coils... ) This is very common material in the upholstery business, and comes in many grades, loop sizes, and thicknesses and strengths.

My driver's seat was sagging to no end, and the culprit (prior to taking the seat apart) was suggested to be "broken springs". When I got the seat apart, it was clear there was nothing broken at all. However it gave me the opportunity, sans pad and covering, to see how all these interior spring parts met, moved and sprung together. When I sat on the raw springs, the front of the seat (which is under your knees) immediately went to the floor; it bottomed out with no additional motion left. I decided that the springs were just too weak--but "replacing" the springs was very invasive as there are welded parts involved and this is beyond my capability. Thus I decided to bolster the existing springs by "siameseing" new spring material onto the existing springs, as well as adding additional. I probably added about 10# of additional springs, all connected with crimp fittings, hog rings and more. With all of this added, moving the seat springing by hand became considerably more difficult, and I thought I had achieved some success. However when I tested the seat again--this time sitting on it once again, it once again totally bottomed out--no additional motion left.

Fitting the foam noodle in the front of the seat, such that this spring material shown curled around it, prevented the seat from bottoming out. There's a bit more firmness to the seat when the springs are damped. Without it, there is no damper. Everyone does it a bit different, but I added full round foam to the front as mentioned, curled it around the sides but had to shave off foam as the foam tapered to the back of the seat bottom. I did not do anything to the seat back as this didn't seem to be much of an issue for me.

Have you ever seen how a car suspension behaves without dampers?

I wanted a bit more firmness and all the additional springs I could possibly add didn't do the trick.