SC Car Regulator sphere pressure

[yoseff]

Been slowly putting the Activa more towards its good state , also by reusing spheres that are near the recommended pressures.
Knowing that SC-car regulator sphere is supposed to be 30 bar (+5 / -10) , what would happen if i reused one there that is 40 Bar?
If i understood well the SC Car system , the role of that sphere is to serve as a "Spring" for the activa rams in a straight line. So maybe that extra 5 bar on top of recommended would make the car more confy on straight line? Could that provoke any issue?
Here i left the pressures for each sphere. My goal is to put all spheres with 5 bar over the original values (on top tolerance) , but having this one with 40 bar, that would be at least for a while with 10 bar over original value.
What's your thoughts?

Tomorrow gonna swap the front and maybe the rear Height corrector for clean ones i have here , and i'm tempted to use the depressurization time to change that too. On a second thought , if something goes less well , i will not be sure from what it was. But that sphere is not hard to reach even in ramps , so i can change it other day

[CitroJim]

The SC/CAR sphere is effectively part of the variable stiffness Anti Roll Bar (ARB) system and is in circuit at all times except when switched out by Activa electrovalve under influence of the Hydractive ECU when it calls for maximum roll correction and maximum ARB stiffness under very heavy cornering.

An extra 5 bars in this sphere is likely to make no appreciable difference; it may make the ARB effectively less rigid under normal driving so your thought it may make thing a little more comfortable is potentially possible but any change in ride may be tiny indeed.

A bit of experimentation in this area may give some interesting results. I've payed with sphere pressures on an Activa in the past and found Hydractive Xantia Estate spheres generally work well.

One thing that makes a significant difference is to ensure both the main and Activa accumulators are both right up to spec. at 62 bars. the Activa one, under the battery, tends to be forgotten and often needs to be custom made as it's of the same fitting as an anti-sink sphere and at 62 bars, unique to the Activa. A standard anti-sink sphere will do at a push but is not ideal.

[yoseff]

The SC/CAR sphere is effectively part of the variable stiffness Anti Roll Bar (ARB) system and is in circuit at all times except when switched out by Activa electrovalve under influence of the Hydractive ECU when it calls for maximum roll correction and maximum ARB stiffness under very heavy cornering.

An extra 5 bars in this sphere is likely to make no appreciable difference; it may make the ARB effectively less rigid under normal driving so your thought it may make thing a little more comfortable is potentially possible but any change in ride may be tiny indeed.

A bit of experimentation in this area may give some interesting results. I've payed with sphere pressures on an Activa in the past and found Hydractive Xantia Estate spheres generally work well.

One thing that makes a significant difference is to ensure both the main and Activa accumulators are both right up to spec. at 62 bars. the Activa one, under the battery, tends to be forgotten and often needs to be custom made as it's of the same fitting as an anti-sink sphere and at 62 bars, unique to the Activa. A standard anti-sink sphere will do at a push but is not ideal.

Thanks, CitroJim for the detailed thoughts.

Main accumulator , instead of 62 is at 65 (Repurposed multi layer front central stiffness regulator)
I need yet to check the front SC/Car sphere. It's indeed the only one i didnt touch till now. I'm specially afraid of the rubber insert going wrong as i do not have any of that specific measure. But that sphere will be checked soon and probably put to 67 Bar instead of the 62.
My goal is to make the Activa a sofa on wheels on a straight line and a go kart on turns

This poor Activa was "a bit" neglected , but will do my best to re-activate him at the highest po$$ibl€ way. Not easy to keep 2 hidropneumatics on the road - always something to do in any of them

Luckly i still have quite a bit of material that will help me in that task (Xantia). Just a few days ago i fitted the SC/Car plastic guides that i had new (If i knew what i know today , would have bought more in that time , but got just two pairs)

Will share the results on the sphere test

[CitroJim]

Yes, the Activa accumulator sphere pipe seal is a 4.5mm one and not so common as the 3.5mm one. So often they are good for reuse multiple times if you are careful with it...

This poor Activa was "a bit" neglected , but will do my best to re-activate him at the highest po$$ibl€ way. Not easy to keep 2 hidropneumatics on the road - always something to do in any of them

You're doing well so far, keep up the good work

Will share the results on the sphere test

Yes, please do! The Activa will never be a 'sofa on wheels' like a good, well sorted ordinary Xantia although they can be very good when well maintained and a bit of selection work done on the best spheres to get a good compromise between handling and comfort...

[yoseff]

In theory , they could be the most comfy ones In a straight line (more pressure in central spheres , "thinner" anti roll bars) while the most effective ones on turns (Cut all the comfort "added pressure" of the spheres)
I imagine this tech added to extremes in a modern C5 Activa... What a wasted opportunity Citroen had...