I've had the same question for my wagon.

I've asked a few of my engineer friends, but get cryptic answers: "Frequency and response would be affected by any changes to the fluid system" was the answer with some caveat about discussing further over beer..

I have 2 spare new (Corteco) spheres right now.
I need to see if there is room to mount them next to the existing ones.
Alternatively I could mount 1 extra with some t-fittings.
There is a good hydraulic shop near by that can make me the hoses and cap for the input line on the extra sphere(s).

I suppose if you consider the absurd and installed 1000 spheres, the load spread among them all wouldn't be enough to compress the gas and the ride would be hard (hydraulic lock basically). So what happens in the more reasonable case where the load is spread among 2 spheres, each deflected only half now, and the fluid passing through 2 valve bodies instead of one, but with only half the action.

Might just have to try and see.

These things look similar to "Pulsation dampeners", that we use in the car wash business to even the output flow from our high pressure piston pumps. The type that I use are rebuildable and have a schraeder type valve so as to allow you to charge the unit for appropriate balance based on your pump output pressure.

Most carwash equipment stores will have the liquid nitrogen to fill your dampener. My dampeners have a 1/2" fpt inlet from your source.

Not sure what the SLS system pressure is, but for our car wash pumps we charge the cylinders at 1/2 of pump operating pressure. Ie. pump pressure 1,200 psi., 600 psi., cylinder pressure.

I have found them to be very long lived, without maintenance.

I now have H&R springs front and rear with Bilstien HD up front and SLS in back.
The front end it toyight.
The rear is sloppy loose even with brand new accumulators and rams that don't leak.

Discussions with people smarter than me indicate that just adding more spheres won't help. Its the damping that needs improving.

Would be neat to be able to have adjustable compression and rebound (in and out) damping for the SLS...

Didn't Citroen have that on some of its models? Could the mechanism be adapted to an MB?

I am reading some Citroen technical manuals and I think the answer is yes.
Some even had a switch to choose the firmness.

An addition restrictor orifie, or a variable flow valve that reduced the speed at which the hydraulic fluid could enter and leave the sphere would reduce body movements, no?

I am going to order 4 unidirectional variable valves. 2 for each ram. One for compression, one for rebound.
The are free flowing one direction and can the flow restricted or stopped the other direction. This should give me total control of the in and out. It might be tough to perfectly match the left to the right.

Hoping for less squat, more body control, and if it doesn't work I can just remove it and get back to some other project.

It would be a lot simpler with one single restrictor valve that would control both directions.

I ponder at the necessity of controlling both directions for a normal street car.
Overkill?

** But it seems a lot of the simple valves are uni-directioal anyways. They restrict one way, and free the other.
The tractor guys use 2 valves to control hydraulic items.

Along these lines: http://www.princehyd.com/Portals/0/products/wolverine/WolverineInlineFlowControl.pdf

I finally got the balls together and did my SLS modification.
Used a Parker hydraulic restrictor valve (variable) and a bunch of fitting shenanigans to put it all together.

I have the dial closed down about 4 turns now and the ride is firmer, no harshness, less squat on acceleration and less wagging over big undulating bumps (A sensation that really chapped my hyde). My car has H&R springs with new rams and new accumulators so everything was working as well as it could, just wasn't firm enough. Now I can dial it in how I want.

One if the little bastard fittings is leaking, so I will fix that tomorrow.

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Attachment 105720