Glad to see randy Pobst's impression on the F Type confer with mine on both the XK and theF Type. I would buy another XK if I knew I could correct the poorly setup spring rates by getting a slightly lesser spring for the rears. Car is too damn stiff and thus darty and rear end happy. I'd love to put XK springs on an XKR for example.

 

Agree with you fully regarding the rear spring rates being far too stiff on the XK(R). You can not put the power down coming out of corners without the rear end jumping sideways on you. Those springs will not allow sufficient weight transfer to happen.

I've been blaming the Jaguar suspension team for the setup for years now. Fun cars to drive but, with 510HP (XKR), you have to have a superlight foot on the accelerator if you don't wish to leave the road backwards... What both the XK and XKR need is much lower spring rates and much stiffer sway bars at the rear. The XKR is definitely more neutral in cornering than the XK but, those spring rates are far too high.

 

TATA needs Lotus to teach them about suspensions.

 

I've only owned my '12 XKR for a short time but this is by far my biggest gripe! I'm surprised none of the aftermarket spring makers have not offered a solution to this issue...or maybe they have and I just don't know about it? Any of you long term owners know of a fix?

 

So I'm wondering if the springs from a regular XK would work? Seems like they would be a bit softer?

 

The spring rates and bars are well balance front to rear, and a lapping day on a road course is a great place to confirm that. The electronic damper's low speed valving however probably is off, along with the overly aggressive electronic throttle, and both contribute to the rear wanting to step out with little provocation. It's this part of a damper's valving that is responsible to control the tire's contact patch under weight transfer during cornering, braking and acceleration. High speed valving is responsible for handling bumps. The short and stiff sidewalls also don't help add compliance to the suspension to more securely handle weight transfer. Lots of issues that Jaguar doesn't seem keen to improve, and they instead play up the drift car attitude. Pity.

 

^ This is often the most overlooked part of any suspension. Short sidewalls may look great, but they are counter productive in the real world.

The truth is, you can't hold Jaguar to blame for providing buyers with what they want. Jag buyers today are far more worried about appearances than performance. Hence big rims and rubber band tires win over smaller rims and a more controllable (and in my opinion , preferred) connection with the road surface.
All you need to do is choose your poison. Big flashy rims and a freakish scary connection to the ground, or a solid connection and less flashy looks...

 

No one is more against the low aspect ratio tires (short sidewall) than I am. I've been complaining about this trend for many years. For all practical purposes a set of higher aspect tires should provide the same or better actual street performance as they absorb pavement irregularities much better than the ultra stiff sidewalled low aspect tires.

Having said that, however, there are examples aplenty to show that you can get a more compliant ride even with those low aspect tires. The new Stingray comes to mind as an example, having superb handling and very good street ride qualities with the magnetic shocks.

I also suspect that Bruce H. is correct in his assertion that the low speed damper valving performance with the Jaguars is also to blame. In my XJL the damper valving is terrible and in the XKR it could also be better. However, I would still prefer a sizable reduction in the rear spring rates from the present 500+ lbs/inch to something closer to the 300-400 range, combined with a 3/4" sway bar. That would produce a similarly neutral handling but, more weight transfer to allow the rear tires to bite. In my admittedly much lighter Twin Turbo RX-7 the rear spring rates are 275 and, boy, does that suspension bites coming out of corners...

BTW - Bruce; I finally sold my RX-7 with heavy heart to a true enthusiast. It was an absolute killer car, nothing could touch it on the streets BUT, I was simply not driving it or enjoying it at all. So, poor me, down to 4 cars now, 3 of them Jaguars :-)...

 

Well, congrats! There comes a time where you have to let go, and I guess you found it. Hopefully the new owner will enjoy, appreciate and respect it. And I bet you'll be happy to have the garage and driveway space. Now think of the new toy you'd have room for when you turn in the XJ!!!

 

What suspension modifications were made to the XKR-S GT that made it put the power down so well. Are the rear springs softer? I know it has a different sway bar. I had my second year annual service done today with 5,000 miles on the clock and my rear tires only have 7/32's remaining--I don't track and drive the car reasonably. My brake pads have 90% left.

 

I don't know the detailed suspension differences in the GT. But, if I remember correctly, the GT test cars came with R-rated semi racing tires which alone would make that difference in additional traction.

Yeah, it is hard to keep those rear tires from wearing out quickly. My XKR has 6K miles on it, front tires are almost like new, rears at least half gone. Price of having so much power and torque transmitted to the ground even just from spirited street accelerations.

 

Rears wearing out is also a sign that Traction control is constantly intervening. Driving these cars with TC off is pretty futile! I felt a bit like an *** pointing out these shortcoming to my salesperson recently. He got very defensive when I suggested the ride in our new to us 2012 Mazda MX5 Miata GT-PRTH is actually better than the XK. He said of course your Miata is a real Sports Cart and the XK is a GT. Kind of backwards, wouldn't you say?? GT cars should not beat you up, they should take a set in a corner and inspire confidence regardless of the road under you.
After 2 trips 2 Maine this summer in our beautiful XK, my wife, to my dismay told me she'd rather take the Evora next time as its more comfortable on long trips. So much for our XK being used for trips to Florida etc. So when it was totalled and I asked her if she wanted it replaced she gave me an adamant NO!. She'd owned Jags for the past 12+yrs and considered herself a Jag person but....... Maybe they get a new team on the XE to learn about modern suspensions. I predict with in a year or 2 they completely rework the F Type suspension. It will be a nightmare at the track! unless being sideways rocks your world.

 

I believe the R-S GT has suspension based on the F-Type. To improve the standard XKR, you could try & get the Dynamic Pack suspension components.

 

I would prefer that ride to be softer, more GT-like in my XKR but, altogether not complaining in view of my XJL that supposed to come with a luxury car ride. One of the times I took it back to the dealer to investigate my ride complaints, they gave me a base Hyundai Sonata loaner. When I came back to pick up my XJL with nothing changed, the dealer rep asked me how was the Sonata. I told him that I wished my XJL would ride anywhere close to as smoothly on the highways.

He laughed, thinking that I was joking; sadly, I was NOT.

 

I have a 2002 S-type 3.0 V-6 and need to replace my shocks. Getting confused if I need the one with or w/o Electronic Suspension Control. I have no wires coming out the top of my shocks, so I'm assuming w/o. Looking for the smoothest ride I can get, any recommendations on which one to buy?

 

I'd suspect you're right - no wires = no electronic control. As for a recommendation, you'd be better off asking on the S-Type forum:

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