If you have "boat-like handling" it is not due to the OEM set-up, something is wrong.

 

Hah that might be abit of an exaggeration, probably tired coil springs more than anything after 210000km but I'd rather have stiff responsive suspension unless its so harsh it starts causing metal fatigue. Wouldn't poly bushings and soft shocks even each other out?

 

I have never run Poly on a jaguar so l can't comment too much on that but l can say my current setup is stock XJRS setup (rubber bushes/bilstein shocks) and would not change any part of it.

 

Vancouver
Baxtor is right. A properly suspended XJS will run arrow straight, track on long fast bends like a guided missile with no steering correction needed, corner surprisingly roll-free, and be very responsive to steering inputs.
Having said all that, you only need a few of: duff shockers somewhere among the 6, deteriorated bushes in the front suspension, play in wheel bearings, some poorly balljoints among the 6, deteriorated rack mounts or worn rack, rear end fulcrum play, and most importantly and often forgotten, grooved stub axles, to spoil it.
The solution is not rock hard shocks, rock hard bushings, or solid springs. Just spend the money doing all of the above using OEM quality parts and caramba, you'll be there.
Look at Macdoesit's recent post. When they come right it is just amazing.

 

What if you're purposefully trying to stiffen the car up beyond stock settings? I'm sort of in this same boat at the moment myself. I'm going to be putting poly bushings on the steering rack soon, and the sway bar, and was considering doing at least the front lowers with it as well. I like the car's GT heritage but I'd prefer a stiffer, more confidence-inspiring handling profile, which I currently do not have in the slightest. Admittedly, most of my issues seem related to steering slop; this car is a bit tighter overall than my other XJS was (an 88 model) but not by much.

I've also looked into changing out wheels, maybe lowering the car, getting stiffer shocks/struts/etc. Yes, I know that it will change the personality of the car, but that's kind of what I'm going for. What I don't want to do is harm the car while trying to make this happen.

Jess

 

I am a purist, of sorts, and OLD and Grumpy,

BUT,

Do the suspension, as Greg has mentioned, and do it ALL, and do it RIGHT.

Repeat in another 25 years.

They are NOT a Corvette riding car, FAR from it, and attempts down here to do what I read here have cost money, spoilt the cars basic design, and the owners have mostly returned to OE components, and the joy of that car is returned.

In fairness, I altered a few things in the PRE Forums days, no other reference than to try it out, and that is where I came up with the suggestions I mentioned above. I applied all those same spec items to the Sedans we owned at the time.

I run Gabriel shockers on all the XJ cars, includung the XJS's, and they ride sweet.

I have been amazed at the amount of improvement ALL the cars returned when ALL the items are addressed as a whole. A SMALL amount of wear here, a bit of slop here, and so on, shows nothing major, but a wafting handling car. Grazing with a bit here and a bit there will never get the total Jaguar experience.

As mentioned, I drive HUGE miles, FAST and HARD, and even back in the MK7 days, the stock set up did the trick without fuss or moments of "oh s&^t" that was not a good feeling.

The MK10 (Whale as its known better) took some sorting, but once all the Metalstic rubber bits I needed were sourced, that thing was a sweet ride at 100MPH on any road.

Stiffer shockers will ruin that car for what it was designed for, and the GT is for Grand Tourer, not a racing machine, sorry guys, you need an XJR/XKR for that one in MY opinion, but then age makes one mellow a tad I am told.

My HE was as Greg stated, FAST, SMOOTH, and tracked true on any surface, even our endless Gravel roads. It was a pleasure to drive anywhere, and the X300, X300R and now the S Types, do NOT come within a bulls roar of the panache that car had.

 

What if you're purposefully trying to stiffen the car up beyond stock settings? I like the car's GT heritage but I'd prefer a stiffer, more confidence-inspiring handling profile, which I currently do not have in the slightest. Understood, but until the car is right OEM, you have no proper idea of what the starting point should be. I would be more inclined to take it stage by stage. There are very good uprated spring kits with adjustable platform shocks available from reliable specialists in the UK, and they do work without ruining the car
Admittedly, most of my issues seem related to steering slop; JaguarSport rack bushes will fix that.
What I don't want to do is harm the car while trying to make this happen. I reckon then, that stage by stage is the way to do it; but unless the car is bang-on OEM to start with, I feel you risk addressing underlying mechanical issues with the wrong remedy.

 

Jess, I can't speak for you specifically but I know a lot of people who equate "good handling" with "no body roll and stiff suspension". Don't fall into that trap ! There's more to "good handling" than just that...especially on a street-driven car.

I'm not saying "don't modify". But be judicious. IMO, the last thing want to do is makes things too stiff.

I'll explain this way:

I have regular opportunity to drive a wide variety of performance-oriented cars, old and new, whenever I want. It's actually part of my job. A lot of these cars, like Corvettes and Porsches, are stiffly sprung. In real world zooming around on curvy roads with rough spots, dips, bumps, pot-holes, etc. I often find myself clenching my teeth a bit, wondering exactly how the car will react...as they can be a bit quirky and twitchy, and sometimes skittering rather than tracking. Driving the same roads at the same speeds in my Jag, however, is a very different experience.

The Jag is absolutely undisturbed when faced with such conditions. I can drive through with total aplomb and with zero apprehension that something quirky is gonna happen. Yes, a bit of body roll. And, no, not absolutely razor-sharp steering. But, all-in-all, very competent.

I'm not saying an XJS corners better than a Corvette or Porsche. Nor am I saying it can't be improved upon. When it comes to mods, though, I'm saying "be careful what you wish for" . You might be tipping things towards the negative side of the compromises.

For example, I'm a believer in adding a rear anti-roll bar and increasing the size of the front anti-roll bar. Not everyone agrees with me on this....with good explanations as to why....but I've always been happy with the results. However, the point here is that, in experimenting with different rear bars, I discovered exactly what I expected to discover: it is very easy to go too far. Going too stiff brought on some very unpleasant results in exchange for just a very slight improvement under a very small window of driving conditions.

Cheers
DD

 

Looking forward to mine being back on the road even more now I’ve read all that. Will have a more or less new car suspension wise including the stub axles and bearings so all combined I should find out how some lucky punter felt in 1989!

 

The first thing to do is to go through the suspension and steering, carefully inspecting all the components for condition and wear. Then replace all of the suspect parts, with stock. The exception would be the steering rack bushings, they should be replaced with poly or Jaguar sport ones.

Then, and only then, should you start thinking about upgrades. IMHO, some slightly stiffer shocks might be appropriate, and the sway bar mount bushings might be suitable for poly.

I had Bilsteins on my previous XJS convertible, and liked them. Not harsh enough to ruin the ride, but they do sharpen the handling a little.

You've got 3 XJS's, and an important question is which one we're talking about. Is it the convertible? I see a mention to 89. In that case forget about sharpening the handling, the structure is too floppy. All you'll do is really ruin it. Just return it to stock but refreshed.

One thing which will help most on a pre-92 convertible is to fit the post-92-style front and rear X braces to stiffen the structure. I believe Harvey Bailey make ones that bolt on.

 

my sway bar poly after 2 years ,. red.

went to MOOG blue sway bar kit, cheap $15. usd.

 

Yep, seen that a few too many times.

Sadly MOOG packed up their bat and ball and left OZ, so no more MOOG down here.

 

Is that part number on the box correct? I just googled that and it's a Ford kit. I love hearing about cross-reference parts and would love this to be accurate.

Jess

 

A lot of those Moog end link kits are rather generic; no doubt designed to work on many different cars. I've used them on Jags and other cars.

Sometime manufacturers play things a bit fast-n-loose, though. The Moog end link listed for a Datsun 240Z looks just like the one pictured but in that case wouldn't come close to working

Cheers
DD