I'm an XKR kind of person but finances limited my recent purchase to a 2008 XK convert. My plans are to enjoy it for what it is until this time next year, after saving my pennies I hope to be in a position to fulfill my xkr desire.
I've only driven it @ 100 miles, it is quicker than my 2005 xk8 but the one time I zinged it up to 80~110(mph) one one of my many texas hillcountry open roads it wallowed all over the place and the shocks did double bounces before settling down at all. Is this what I am to expect?
Will the can learn some of my rather high speed driving traits and settle down or can I do some reprogramming or?????
help please

wj

 

My 2010 XKR 'vert is totally stable and flat up to 180, so I don't know what the problem is with your 2008. You'd better check stuff before playing again.

 

^^^ What Cee Jay said.
Check the dampers/shocks, they can go bad over time (my right front leaked and peed on my garage floor). Since you haven’t owned the car from day one, someone could have replaced dampers with the wrong type (I did that on mine, and the front end got all bouncy, not because the dampers were too soft, but were too hard, because my 4.2 couldn’t control the dampers meant for a 5.0, so they stayed in the firm setting).

 

The xk springs are terrible definitely not designed for 'spirited' driving very very floaty.

The xkr springs are a lot firmer and the xkrs are firmer once again also with a 10mm drop

ive had 3 different styles in my car (xk, xkr & eibach) and after many different trials I had found eibach on front & xkr on rear worked the best.

However if I had my time again I'd go straight for the xkrs spring and dampers

 

Okay thanks...if one was trying to stay on a budget and not make it into a racer of any sort would you suggest either of these would be most beneficial or must they both be swapped out? I don't want to go down 10mm with the roadways I encounter so it would be eibach + xkr for a spring swap...not certain that xkr shocks would function as designed with the XK software, but don't know for certain and really not wanting to be a guinea pig.
thanks for your time
wj
wj

 

If on a budget simply go the xkr springs and retain your shocks as handling will still be dramatically improved however if you do notice any of the shocks weeping change them out.

in regards to calibration it's the same module on the xk and xkr so no issues as to whichever shock you have in your vehicle

 

To the OP: Just make sure you use shocks meant for the 4.2 cars, not the 5.0 ones.

 

and before installing plug in first to check they aren't faulty (seen this happening a few times with brand new shocks)

 

“wallowed all over the place” is much more than just a springs issue…. heed CJ’s suggestion.

 

There's no software involved, the dampers themselves are the difference. Handling's subjective but I once had the stock suspension over 160+ MPH and found the front end light a floaty, not firmly planted. Others here have made similar observations. Since then I replaced all bushing with poly, tried Eibach springs and finally fitted multi-way adjustable coilovers. Each change was a tradeoff, from a more comfortable controlled ride to a firmer, stiffer, twitchier ride with better high speed and cornering, but still a bit light in the front at high speeds. Aero tuning now.

 

Drive in Sports mode - dampers get stiffer.



Hermann

 

I will try the sports mode.
I drove 50 miles today, if I still lived in Penna I'd be happy with the soft ride and adequate handling but..
I'm in wide open Texas and I can say that the initial turn in a bit soft and then if there are undulations in the roadway the car rides up and down as if I had air springs underinflated and shocks that didn't want to do much dampening, this doesn't work for me. I charged into a great 90 degree sweeper at speed, the car would hold the line but it was almost rolling over the 20" tires...no real drama but obviously I was pushing this thing way beyond its meant purpose in life.
I'll be pulling the wheels in a week or so to do a wheel refinish and brake rotor/pad replacement. At that point in time I'll see what is going on in those dark confines. The car does not feel loose as if something is worn, rather loose as if that is it's design.
In the mean time, where can I source xkr springs?

wj

 

The 4.2 CATS system doesn't work like that it's continuously changing between the two settings depending on the terrain/surface regardless if it's in DS (sports) or not

Also when up on lift check the shocks for any fluid weeping out if so they are throw away .

in regards to sourcing the xkr springs Pacific Motors are pretty good and usually sell the shock & spring as a complete unit if this is the case the installation will be a breeze.

On a note make sure if purchasing complete unit the damper is green in colour which represents xkr (xk are black) also make sure your purchasing from a wrecked 4.2 not a 5.0

 

I'm still not understanding your definition. Are you saying it rides stiff but bounces hard like you can feel your butt going up and down or see water jumping around in a bottle in the cup holder, or bouncy bouncy like a 1970's Cadillac?

 

Sounds like in turns? Sway bars will help with that. As for sport mode on the dampers, correct there's no user setting for that, pull the CATS fuse and they'll default to the firm setting. What I noticed doing that is the dampers went from smoothing the ride and absorbing undulations and bumps to giving more road feel, less dampening of the flaws so they were felt more.

 

You've an '07, not user selectable damper mode. The DS Sport mode is a different PCM map which changes the shift profile of the transmission.

 

rather than bouncy bouncy, let's say it floats up and down like a 70's cadillac (as long as there are undulations in the roadway) not as if there is zero dampening.
wj

 

in turns, on the straights if road undulations...I'm thinking more along the lines of bad shocks. Although I'd like a canyon carver I'm not prepared to spend the monies to upgrade swaybars and basically all related parts to the suspension to match an xkr (remember I want to save my $ in order to purchase an XKR next year, then we'll get serious)
The steering was spot on and I felt as if I could thread a needle but I was constantly fighting the suspension/body movement. I won't have time to check it all out for several weeks but expect to find the 'weeping' shocks. If so I'll replace them and add new urethane sway bar bushings hoping that satisfies my compromised desires. Might browse used xkr parts and determine the cost of those sway bars.

wj

 

wymjym,
How many miles on your XK? Where did it "grow-up"? If it lived in pot hole prone areas it likely has worn joints and bushings.
Paraphrasing CeeJay, a thorough suspension inspection by a highly competent tech is recommended.
My experience is that looks can be deceiving.
Keep us posted on what you find.

Bill

 

Hey Bill,
90K, Oklahoma
we'll see what's up soon, at present it is a very nice smooth ride

wj