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I'm offered a choice of two cars (from different dealers). One has adaptive suspension, the other is vanilla.

The first has 22" wheels, the other has sensible 20" wheels.

My priority is comfort.

The fellow trying the sell me the car with big wheels and adaptive suspension says that the adaptive suspension is a must-have for a comfy ride. My hunch is that the "comfort" mode of adaptive suspension is simply the default mode... that is, the ride that I would get if I had no adaptive suspension.

In this context the 20" wheels would make the greatest contribution to my desired ride quality, no?
 

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MY21 Portofino Blue HSE, Pano Roof, Clearsight Mirror, Air Suspension & AD, Upgraded Cabin Light
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I have 20" wheels and AD which is I think the right combo. AD helps to take out some of the choppiness of air suspension on rough surfaces it doesn't really make the ride any smoother I don't think (but it is difficult to tell sometimes what it is doing). The 22" wheels will have a worse ride I suspect even with AD and will be easily kerbed, which is why I opted not to have them even though they look better.
 

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We have two cars with dynamic air suspension and I don't find either of them especially comfortable on the uneven brick streets in my neighborhood, but both handle better than you'd expect given their weight and height and both are perfectly comfortable on decent roads. In my I Pace with AD and 20 inch wheels, I always dive in Dynamic and not Comfort or Eco.

Oddly, I find myself using the adjustable ride height on the I Pace more than the Velar. Because we get heavy rains in the summer where I live, the drainage troughs can be aggressive in depth and slope. It's handy to raise up the suspension when navigating these. So although you didn't ask about this, there is some utility to the EAS.

Strangely, the best combo for the undulating brick streets in my neighborhood is Dynamic with the suspension raised. Comfort with the higher setting feels bouncy.

As others have said, I think that the 22 inch wheels will detract from comfort more than the suspension. Like E-B, I prefer the 20 inch wheels and AD but lots of folks here have the 22 inch wheels and love them. I'd try to drive both cars over speed humps or brick streets and go with your favorite.
 

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2020 I-PACE SE w/ 22" F-PACE Wheels
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I don't have adaptive dynamics on my current car, but did previously on my 2017 XE. If the various settings made any difference, I couldn't tell.

As someone who went from 20" wheels to 22" on his I-PACE, I can tell you with the utmost of confidence that wheel size will have a much greater influence on ride quality than adaptive dynamics.
 

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MY21 Portofino Blue HSE, Pano Roof, Clearsight Mirror, Air Suspension & AD, Upgraded Cabin Light
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Just finished 480 miles in one day with 20s and no adaptive suspension. My bottom and lower back feel fine.
Not familiar with the ipace setup but to me adaptive suspension has always been about better cornering. Not comfort.
This is a good summary I think. AD will help make the ride selectively harder and help smooth out the way that air suspension works at speed, not help to make it softer.
 

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This is from Jags website

Adaptive Dynamics is a combination of intelligent sensors and continuously variable suspension dampers. The system constantly adjusts the dampers to provide the optimum balance between comfort and refinement at all times. The system adapts 500 times a second to steering movement and 100 times a second to body movements. It analyses acceleration, cornering, throttle and brake pedal activity, as well as kick-down activation on models with automatic transmission. The adaptive dampers can then use this information to constantly adjust and fine-tune to give you a composed ride with maximum control.

I'm wondering what this means exactly: adapts 500 times a second to steering movement and 100 times a second to body movements.
Its not an Active Sway Bar as seen on other cars that will mechanically reduce body roll and road bumps for better handling and smoother ride
Is it more like an the Mercedes Magic Body Control system?
 

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If it’s like the Cadillac system, it is the fluid in the shock absorbers. It contains an electrically sensitive fluid that can be adjusted by raising or lowering its viscosity. So you essentially have the car reading the impacts that all four wheels are absorbing and adjust the four according to what it thinks is happening.
 

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Another note, lets assume there is a marketing blurb somewhere that says adaptive suspension is great for comfort… unless you love them, you are going to be paying for thone 22 wheels 3 times for your ownership period… once upfrent for the up charge, twice for the extra electricity you are going to pay for because they are less efficient and therefor you need more electrons per mile than the 20s and third when it is time for new tires. So unless you live in a market where you think you can get your money back for the 22s and get 20s fitted, its just not going to make you happy dollar wise for a comfort feeling that really can’t be measured between adaptive and not.
 

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MY21 Portofino Blue HSE, Pano Roof, Clearsight Mirror, Air Suspension & AD, Upgraded Cabin Light
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Another note, lets assume there is a marketing blurb somewhere that says adaptive suspension is great for comfort… unless you love them, you are going to be paying for thone 22 wheels 3 times for your ownership period… once upfrent for the up charge, twice for the extra electricity you are going to pay for because they are less efficient and therefor you need more electrons per mile than the 20s and third when it is time for new tires. So unless you live in a market where you think you can get your money back for the 22s and get 20s fitted, its just not going to make you happy dollar wise for a comfort feeling that really can’t be measured between adaptive and not.
You will pay a 4th, 5th etc time too when you kerb the bloody things. The 20" wheels seem to be super resilient I have caught kerbs a few times now despite the 360 camera and other parking aids. On the 20" wheels the tyre is very protective of the wheel and they have always emerged unscathed.

As a long time owner of cars with very low profile tyres I know that on my previous cars (and an iPace with 22" wheels) this would have scuffed them and required refurb (and some of the 20" wheels appear not to be refurbable much like this on my 2011 model GTR.
 

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19 I-pace HSE Polaris/Fuji white with most options and a lot of accessories
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If it’s like the Cadillac system, it is the fluid in the shock absorbers. It contains an electrically sensitive fluid that can be adjusted by raising or lowering its viscosity. So you essentially have the car reading the impacts that all four wheels are absorbing and adjust the four according to what it thinks is happening.
Nope. See below quotes from workshop manual.

ADAPTIVE DAMPING
Adaptive Damping (AD) is an electronically controlled suspension system that continuously adjusts the damping
characteristics of the suspension shock absorbers in reaction to the existing driving conditions.

The system is controlled by the Chassis Control Module (CHCM). The CHCM receives signals from 3 accelerometers, 4
height sensors and other vehicle systems to determine:
  • Vehicle state
  • Body and wheel motion
  • Driver inputs.
These signals are used by the CHCM to continuously control the damping characteristics of each adaptive shock
absorber to the appropriate level. This provides the optimum body control and vehicle ride.

ADAPTIVE SHOCK ABSORBERS
The adaptive shock absorbers are nitrogen gas and oil filled monotube units. The adaptive shock absorbers are
continuously variable, which allows the damping force to be electrically adjusted when the vehicle is being driven. The
adaptive shock absorbers provide the optimum compromise between vehicle control and ride comfort.

The adaptive shock absorbers have an electrical connector on the end of the piston rod, in the center of the top mount.
In each adaptive shock absorber, the damping adjustment is achieved by a variable orifice operated by a solenoid. The
orifice is used to open up alternative paths to allow oil-flow within the adaptive shock absorber. When de-energized the
bypass is closed and all the oil flows through the main (firm) piston. When energized the solenoid moves an armature
and control blade, which work against a spring. The control blade incorporates an orifice which slides inside a sintered
housing to open up the bypass as required.

When the adaptive shock absorber is compressed the oil flows from the lower portion of the adaptive shock absorber.
The oil then flows through a hollow piston rod, which is a separate soft (comfort) valve. The oil then flows through the
slider housing and orifice and into the upper portion of the adaptive shock absorber, thereby bypassing the main (firm)
valve. In rebound the oil flows in the opposite direction.

In the firm setting oil flows through the main (firm) valve only. Although when the bypass is opened by variable amounts,
the oil flows through both valves to provide a pressure balance. When fully energized the solenoid moves the armature
and therefore the slider to the maximum extension and opens the orifice completely. The adaptive shock absorber
operates continuously between these 2 boundary conditions.
The solenoid in each adaptive shock absorber is operated by a 526 Hz Pulse Width Modulation (PWM) signal from the
Chassis Control Module (CHCM). The CHCM controls the PWM duty ratio to provide 1.5A to operate the adaptive shock
absorber in the soft setting. When de-energized (0.0A) the adaptive shock absorber is in the firm setting. The current
varies continuously as required to increase and decrease the damping individually in each of the adaptive shock
absorbers.

The workshop manual also has pictures depicting the operation of a shock absorber valve.
 

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I'm offered a choice of two cars (from different dealers). One has adaptive suspension, the other is vanilla.

The first has 22" wheels, the other has sensible 20" wheels.

My priority is comfort.

The fellow trying the sell me the car with big wheels and adaptive suspension says that the adaptive suspension is a must-have for a comfy ride. My hunch is that the "comfort" mode of adaptive suspension is simply the default mode... that is, the ride that I would get if I had no adaptive suspension.

In this context the 20" wheels would make the greatest contribution to my desired ride quality, no?
I think you're absolutely correct. For comfort, 20" wheels and forget about the rest. Could be that AD helps the 22s ride a little better, but if comfort is your goal it's 20s for the win!
 

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I'm offered a choice of two cars (from different dealers). One has adaptive suspension, the other is vanilla.

The first has 22" wheels, the other has sensible 20" wheels.

My priority is comfort.

The fellow trying the sell me the car with big wheels and adaptive suspension says that the adaptive suspension is a must-have for a comfy ride. My hunch is that the "comfort" mode of adaptive suspension is simply the default mode... that is, the ride that I would get if I had no adaptive suspension.

In this context the 20" wheels would make the greatest contribution to my desired ride quality, no?
Apparently I’m one of the weirdos that thinks the 22” wheels with Michelin A/S3+ and AD and the car set to dynamic is a wonderful “close to sports car” ride. I drive daily and it works really well even in Seattle’s potholed streets.
 

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Apparently I’m one of the weirdos that thinks the 22” wheels with Michelin A/S3+ and AD and the car set to dynamic is a wonderful “close to sports car” ride. I drive daily and it works really well even in Seattle’s potholed streets.
Very much enjoying my 22s and Pirellis. Set to light load, ride/handling compromise is fine.
 

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Nope. See below quotes from workshop manual.

ADAPTIVE DAMPING
Adaptive Damping (AD) is an electronically controlled suspension system that continuously adjusts the damping
characteristics of the suspension shock absorbers in reaction to the existing driving conditions.

The system is controlled by the Chassis Control Module (CHCM). The CHCM receives signals from 3 accelerometers, 4
height sensors and other vehicle systems to determine:
  • Vehicle state
  • Body and wheel motion
  • Driver inputs.
These signals are used by the CHCM to continuously control the damping characteristics of each adaptive shock
absorber to the appropriate level. This provides the optimum body control and vehicle ride.

ADAPTIVE SHOCK ABSORBERS
The adaptive shock absorbers are nitrogen gas and oil filled monotube units. The adaptive shock absorbers are
continuously variable, which allows the damping force to be electrically adjusted when the vehicle is being driven. The
adaptive shock absorbers provide the optimum compromise between vehicle control and ride comfort.

The adaptive shock absorbers have an electrical connector on the end of the piston rod, in the center of the top mount.
In each adaptive shock absorber, the damping adjustment is achieved by a variable orifice operated by a solenoid. The
orifice is used to open up alternative paths to allow oil-flow within the adaptive shock absorber. When de-energized the
bypass is closed and all the oil flows through the main (firm) piston. When energized the solenoid moves an armature
and control blade, which work against a spring. The control blade incorporates an orifice which slides inside a sintered
housing to open up the bypass as required.

When the adaptive shock absorber is compressed the oil flows from the lower portion of the adaptive shock absorber.
The oil then flows through a hollow piston rod, which is a separate soft (comfort) valve. The oil then flows through the
slider housing and orifice and into the upper portion of the adaptive shock absorber, thereby bypassing the main (firm)
valve. In rebound the oil flows in the opposite direction.

In the firm setting oil flows through the main (firm) valve only. Although when the bypass is opened by variable amounts,
the oil flows through both valves to provide a pressure balance. When fully energized the solenoid moves the armature
and therefore the slider to the maximum extension and opens the orifice completely. The adaptive shock absorber
operates continuously between these 2 boundary conditions.
The solenoid in each adaptive shock absorber is operated by a 526 Hz Pulse Width Modulation (PWM) signal from the
Chassis Control Module (CHCM). The CHCM controls the PWM duty ratio to provide 1.5A to operate the adaptive shock
absorber in the soft setting. When de-energized (0.0A) the adaptive shock absorber is in the firm setting. The current
varies continuously as required to increase and decrease the damping individually in each of the adaptive shock
absorbers.

The workshop manual also has pictures depicting the operation of a shock absorber valve.
 

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Wassup Cats,

my dudes all of the above is true however in my view the most important factor is the aspect ratio!

there is a huge difference between a 22" tire that has a 35% aspect ratio versus a 40% aspect ratio will ride in terms of roughness!! The widest you can go on a 22" wheel to maintain the 40% aspect ratio is 265.

so 265/40/r22.

I've been there, never again. 275/35/r22 looks cool but the ride is straight up awful.

My new Nittos are awesome!! These tire sizes are not that hard to find. Shop around and consider the Japanese brands. shop around!! shop around!!!

I know for a fact Continental makes a tire that fits.
 

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19 I-pace HSE Polaris/Fuji white with most options and a lot of accessories
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1,325 Posts
Is anyone able to tell me how to get a copy of the workshop manual quoted here?
You need to create an independent operator account at Home | TOPIx
Then click on "browse all"
Then click on "Documents"
Then click on "Workshop Manual"
Then click on "Workshop Manual" under that
Then click on "OK"
Then go through the process of getting a paid subscription for a period of time.
Then tediously download each section of the manual. There is nothing to click on to download the entire manual at once.

That's the list of main pieces to click and do. I may have missed something for a new person going through this. It should be obvious as to what to do for anything I missed.
 
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