What exactly is the point of CVD?

Slightly facetious question perhaps, but I'm trying to find justification for keeping CVD on my 2011 L322 vs deleting it.

In my mind, I struggle to think of a scenario where I want the ride in my Fatty to be anything other than "as soft and comfortable as possible".

I don't see turning a corner in a Range Rover as a case for stiffness, I want to ease myself around, not race. Is it a case that this feature is there to compete with the BMW X5 or whatever, making the RR a "high performance sports car"?

What am I missing? I'm planning to replace the shocks on my 4.4 TDV8 with those from a 3.6 TDV8 (and use IIDTool to stop the car complaining). Any reason not to? For example, is the CVD in its softest setting actually more forgiving than the standard damper?

There is a lot of chat about changing "backwards" to the earlier L322 V8 struts there is also chat about recalibration over a drive on the road.
IID has a facility to do it I am sure.

I take it you find yours a bit harsh?
We like ours and it works well on our potholed roads and the smoother main roads. Ours to us drives fine and comfort is fine and has been commented on by many who are comparing to their car (not RR)on the same roads (we also are probably faster than them).

If you drive it for comfort then the active dampening will not get the signal to "stiffen" a strut so maybe a previous owner has tampered already and made it worse.

So as they say measure twice before cutting with the axe .

J

marjon said:

There is a lot of chat about changing "backwards" to the earlier L322 V8 struts there is also chat about recalibration over a drive on the road.
IID has a facility to do it I am sure.

I take it you find yours a bit harsh?
We like ours and it works well on our potholed roads and the smoother main roads. Ours to us drives fine and comfort is fine and has been commented on by many who are comparing to their car (not RR)on the same roads (we also are probably faster than them).

If you drive it for comfort then the active dampening will not get the signal to "stiffen" a strut so maybe a previous owner has tampered already and made it worse.

So as they say measure twice before cutting with the axe .

J

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Thanks for your feedback John.

I checked with GAP and they said the adaptive damping calibration is only for pairing a new module to the car - it does nothing to damping settings, thus running it over different terrain has no effect other than placebo.

I think my issue stems from the fact that it's making decisions to stiffen the damper... and I can't think of a single scenario where stiffer is better, other than very fast cornering.

I was considering whether my dampers are worn out (only 90k miles though, seems a bit early) and figured I would be paying double for CVD dampers (vs non-CVD) for a function I can't see value in.

I suspect it makes a bigger difference than you realise when cornering.
I wonder what happens if you unplug the top? You'll get an error, but it must behave like a normal one because there's no power to make it stiffen?

Can you run live data and record a graph to look closer after.

Is there a diff in price between CVD and Non? I would check that first.

jeremy156 said:

I think my issue stems from the fact that it's making decisions to stiffen the damper... and I can't think of a single scenario where stiffer is better, other than very fast cornering.

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Leaky bag???

We had new bags around this year so age, mileage could be argued as immaterial if on normal road conditions.

J

kermit_rr said:

I suspect it makes a bigger difference than you realise when cornering.
I wonder what happens if you unplug the top? You'll get an error, but it must behave like a normal one because there's no power to make it stiffen?

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Or softer even. Think default is stiffest.

J

marjon said:

Or softer even. Think default is stiffest.

J

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No idea but perhaps that's why you get a harsh ride when the wires break
It works by inducing a magnetic field on the metal content of the fluid, i think

kermit_rr said:

I suspect it makes a bigger difference than you realise when cornering.
I wonder what happens if you unplug the top? You'll get an error, but it must behave like a normal one because there's no power to make it stiffen?

Click to expand...

Sadly it's the opposite... with no current to the damper is stiffens.

marjon said:

Can you run live data and record a graph to look closer after.

Is there a diff in price between CVD and Non? I would check that first.


Leaky bag???

We had new bags around this year so age, mileage could be argued as immaterial if on normal road conditions.

J

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With live data showing a full 1.5A to each corner on the flat, it's still harsh - sometimes even "crashy". Makes me think something is broken.

Pretty sure Sam's motor machine YouTube channel addressed a harsh ride at some point, might be worth looking thru his videos to see what he did?

Tyre pressures?

Mark Piercy said:

Tyre pressures?

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And type of tyre.

I'm new to range rover ownership so this may not be accurate its just what i have found in my experience, when i bought the vehicle I checked my vin online to find out the spec of my rr when new and found that it wasn't originally fitted with the 20" wheels it currently has on and the IID tool confirmed that the wheels were set as 19". Being a bit ocd i decided to change the wheel size and the tyre profile to be correct using the ccf file tool on IID and did notice the ride seemed to change, again I'm new to the vehicle so didn't have much to compare to but in hindsight the vehicle didn't seem to like cornering on the road as much as it does now, at the time i put it down to just how rr are, it seemed to be unsettled in corners and gave no confidence meaning i was backing off to a much slower speed than i expected to but going from a sports car to a rr i thought maybe i just had to get used to it. However, since changing the tyre/wheel size there's been an improvement and i can now carry a good (normal) speed through a bend and the lack of confidence has gone.
my advise would be to check the tyres fitted match what the vehicle thinks is fitted before changing too many parts as there maybe preset calculations it does for suspension depending on the tyre profile during cornering which would make sense to have all the tyre measurements adjustable rather than just rolling circumference for the speedo. For example if it knows you have lower profile (stiffer sidewalls) then it would change how it stiffens the suspension when it sees steering input as apposed to higher profile (softer sidewalls)