Hi there. In my little collection of Jag’s I have a 2008 XKR-S 4.2 Coupe. Wonderful car but the ride is somewhat too stiff for me at my age. So I am thinking about how to soften the ride. Several options come to mind and I would love to have your thoughts and insights on whether or not each one of them will help to achieve to objective:

1. Swap the progressive Bilstein springs to those of a regular XK coupe or cab
2. Swap the stabilizer bars to regular ones
3. Swap the bushings to softer ones
4. Swap the XKR-S suspension control module to the regular XK coupe version
5. Swap springs and dampers to XK Version ($$$)
6. Change the tires and rims to get more sidewall ()

Looking forward to your thoughts!

 

The car should feel soft, when it needs to be soft.

Before you go the path you are thinking I would want to confirm the state of your car.
Do you have the original springs and have they “settled”? Was the car lowered?
I understand the usefulness of the higher sidewall tires and undoubtedly the ride would be without the jarring feel if you moved to the 19s.
Also typically the low profile S rated tires have a stiffer sidewall. Let alone the stiffness of aged tires. Time for tires?
Some over inflate. At times I may run the tire pressures up to 10% down.
Jaguar bushing are engineered to be soft. Was it converted to poly bushings?
And don’t run the car in sport mode as that will not engage the soft damper setting.

An ‘08…. are the original dampers installed? Are they in good shape?
Lastly, at the last time you had the suspension looked at, were the suspension bolts tightened to torque spec, once the car was sitting at ride height? Or, while up on the hoist?

Its a GT and not a sports car. It should be behaving like a GT for you.

 

Thanks Guy. The car is all stock with the firmer setup that Jaguar built into the XKR-S Version. Stiffer dampers, springs and bushings as per their own description. I have bought a set of XK convertible springs on eBay and wonder whether they may already deliver a slightly softer ride vs the progressive bilstein stock springs with everything else unchanged.

 

I do know your car well. The default state for the damper is the hard setting. I’m surprised the soft setting is not sufficient… or is it being activated?
Don’t underestimate the effect tires can have.
I’d be trying 19s, softer tires, very slightly under inflated and ensuring the suspension isn’t over torqued first. Then perhaps the smaller gauge spring set.
What is the state of your springs and dampers? Many xkr owners would be interested in swapping…

 

I have a 2008 base conv. I disliked the oem springs/shocks because the soft setting was far to soft for me. I installed a set of xkr springs/shocks and finally am happy.
From your posting I'm pretty sure you would find the oem xk assemblies to your liking.
wj

 

Trade your XKR-S for a XKR....

 

But is it BRG? or JRG?

 

I have gone through every single combination of springs including xk,xkr,xkrs and admesh aftermarket springs . They all serve a specific purpose or xk- best for long luxurious driving trips but offer very little in the handling department too much body roll , admesh great track days but bone jarring on public roads .
Personally I found the xkr springs to hit that sweet spot in terms of handling and road comfortably

 

Softer shocks. Bilstein B-4. Much better.

 

XKR to XK suspension swap for a softer ride.

 

De-tuning an R-S shouldn't be a thing, you take away its soul.
Maybe sell the R-S and buy an XKR AND an XK. The price points will even out nicely.

 

The simple mild change would be a higher sidewall tire.

 

Ranchero did exactly this on his 19s beefed up the sidewall profile seemed to do the trick

 

What brakes did the 4.2 XKR-S have? The 400 mm Alcons? Is it possible to go down a wheel size from the 20s to 19 with these?

The OP is in Germany and simply putting the wrong sized tyres on the approved rims will not go very far here even if they look like they fit.