Maybe I missed it, but I didn't find anything in the last few years on upgrading the suspensions on these cars. I'm pretty sure my upper bushings are worn out (if not destroyed), as I'm getting some bad creakage going over bumps from the back, on the driver's side especially. One corner of the car is also leaning and it doesn't sit perfectly level anymore. At 135k mi. and as my daily driver, I'm planning to upgrade the whole suspension. I'd prefer something stiffer in the bends, and sitting about an inch lower. What should I be looking at?

 

I found upper bushes lasted around 25k to 30k miles on both my XK8's. If you haven't done them yet, you've had more than your $$'s worth!

Several members have lowered their XK8's. I'm sure they'll be along soon with recommendations.

Graham

 

Graham,

How does gradual wear on the front suspension bushings eventually affect front tire treadwear? Are we more likely to see increased treadwear on the inside portion of the front tires when the bushings are shot?

 

There are several options for springs. Mina gallery is popular. I personally went with an Adamesh set which has a smaller drop than most (~20mm). There is actually a set of H&R springs in the classified section that just came up.

Upper shock mounts are a must.

I like the feel of polyurethane bushings and Powerflex has a full set for the XK8/R. There are two versions the "normal" and "black". Black is a harder material, I opted for the normal version. There are some reports of groaning over speed bumps, although I've never had any real problem with that. There is a Powerflex US site, but it seems to be down right now.
Powerflex - Performance Polyurethane Bushes

For shocks, it depends on whether you have the CATS adaptive stuff or not. If you don't, then it's easy and pretty inexpensive. If you do, I feel your pain, as they are about $400 each. BUT with the adaptive shocks there are two models, regular and R package. The R package are a little more firm and I can certainly attest that new shocks will make the car feel worlds better.

You'll want to do the bump stops and boots while you are doing, just to refresh all the parts.

There is a company called UltraRacing that has some sway bars and chassis braces. I can say that the rear sway bar livens up the car.
Jaguar XK8 4.0 (1998) Aftermarket Performance Parts / Accessories / Spare Part - Ultra Racing Product Catalog

Sway bar end links should be replaced. Two options here: OEM which are fairly inexpensive and readily available. Or the XKRacer super titanium over the top model. Expensive, but they sure do look cool.

After all that, you probably need to let your credit card cool off.

 

Charlie,


I didn't see any pricing for those braces. Have you looked into it?


As for the rest of the suspension My car is lowered and I absolutely love it. I cant quite tell you the brand of the springs being they were installed prior to my purchase. But I've driven with and without and LOVE IT. Also no abnormal tire wear. I talked to the mechanic that did the original install and he explained what he did at the time to keep geometry correct..Dammed if I remember but no abnormal wear. Also I had just ordered the powerflex bushings for the front end a few days ago(Black) from the USA website. Was working then. Since I made my xkr a daily driver the NYC roads have taken a beating on the extremely old suspension so Its gettinga complete overhaul. Ill likely have questions one I get started with this. Have seen rev Sams videos so that helps a ton but I'm new to working on this car... but its time...

 

The company is out of Malaysia but they sell on ebay:
ultra racing xk8 | eBay

The cowel brace won't fit an R though.

 

Interested in this also, I saw the H&R springs in the marketplace also found them on eBay for around $330.

They have black and red, anyone know the difference or have any experance with these?

 

I forgot to mention, I have the CATS system, but when I got the car it was unplugged in the spare tire area. I plugged it in, and noticed no difference! If I unplug it again, and just go with non-CATS shocks, will that be compatible? Or do I have to run the CATS shocks regardless due to some fitment thing? I may end up doing the whole lot, but I'll need to tally it all up first. I'm tight on time this summer with multiple projects, so this may be something I load up into the trunk and take to motorcarman for a week next month.

Typically the Jag gets driven about 4-5 days a week, and about 250 mi. Still, I wouldn't mind a firmer ride if it makes it that much more enjoyable. I've also heard about adjustable Konis? I ran those on a previous car and loved them, also with H&R Sport Springs. Maybe I should just do all of that again. Cool that it's offered on these as well. I don't want to kill the ride with a race setup, but probably want to get closer to that than where I'm at now. I last came out of a Porsche 944 Turbo before my XKR- making the XKR into a bit more into a handling dynamo with this engine would be superb. Sway bars, end links for sure, and chassis braces also under consideration. I have saved that Ultra Racing lower unit in My eBay for awhile.

 

The fit is the same, so if you unplug the control then you can run the less expensive non active shocks.

I do notice a difference with the CATS in soft or firm mode. In firm mode it only changes the rebound setting, not compression, so it makes the car feel sort of bouncy on a strait road. It is harder to tell one drive to he next, but if you fit an on/off switch where you can change while driving, the difference is more noticeable.

The only real advantage of the CATS shocks that I can see is that they are firmer than standard. In particular if you can find the R package version of them. High price to pay though, so really a matter of preference and what your wallet can bear.

Loading up the boot with parts and having a professional do the installation is something to consider. I did the front myself but for the rear you need to drop the subframe, which I wasn't wanting to try on the ground, by myself. Plus the subframe bushes need to be pressed in.

Took a bootload of parts to the shop just this week in fact. Springs, shims, bumpers, shocks, all new bushes and a rebuilt diff with a quaife in it.

 

Putting the polyflex bushings will make a HUGE difference if you change the upper and lower control arms at the same time. New sway bar end links and bushings will tighten it up as well. Don't forget to look at your tie-rod ends too.

 

With stiffer springs you should also getstiffer shocks to have it work together right. I have not seen any CATS of theshelf that offer this, and as I personally like the cats option I went foradjusting the stiffness of the original CATS shocks, and that brought a much betterbalance overall with a firmer feel, yet still comfortable enough for a GT.

 

Andre


Curious if the place that did your revalving was in the states. I recall the post from awhile back. And do they still offer that. If not can that information be shared with a nother company that rebuilds shocks?


Thanks!


Damon

 

Here is the old thread with some more details:
https://www.jaguarforums.com/forum/x...shocks-112799/

I haven't been in contact, but don't see any reason he wouldn't do it anymore (but better to check). Here is his linkedin profile from where you can send an email (don't want to post his private mail here).
https://www.linkedin.com/pub/jurgen-verstoep/8/8ab/436

So far I have not heard of any one else doing it, but I am of course not looking at that anymore.

 

It looks like the H&R Sport Springs are pretty easy to come by, but where does one get the Koni (possibly adjustable) shocks?

 

Haven't seen those available in a very long time unfortunately, not sure they are even made any more.