Hi All, long time.

I've finally found time to go about my front subframe replacement project that has been languishing since 2017. In truth I bit off way more than I could chew & it's been a millstone round my neck all this time, & has made me feel a bit depressed not driving it. Feels good to be working on the Jag again though, & i;m determined to see it through. I'm almost at the point of bolting shiny things together! (I finding out i've lost bolts!)
Does anyone have an opinion on a spring / shock / bushes combo that keeps the XJS ride quality but inproves handling a bit?
I have a 1989 V12 with the sportspack, so it already has the good (more solid) steering rack bushes. I presume it came with the sportspack springs/shocks, & would like to retain/improve this combo if possible.
I need to buy new upper/lower wishbone bushes, front springs & front shocks.
I'm currently thinking the Bilstein Yellow B6 front dampers might be nice ones to go for (available on BritishParts), with the standard springs, unless anyone would recommend something else?

 

2 Bilstein Yellow's up front
4 KYB silver out back
Solid Alu or hard eurthane rack bushes P/N SPF0083K .. Since you already have the sports pack, add 1 to the 3rd mounting point which is unbushed.
Eurathane bushes on the small end of the trailing arm only. P/N SPF0789K
New OE rubber bushes everywhere else.
This is an on street and on track tested.

This stage 1 setup will offer up tremendous increase in precision and rewarding driving dynamics and with no added harshness

SPF0789K

 

I used KYB shocks all around, and Superflex poly on almost everything else except upper inner? Front bushings, I forget but theres some parts of the front that need to stay OEM to absorb the road shock.

Recently my poly radius arm bushings failed, those were not superflex which is why. Rear radius arms now fitted with OEM large / Superflex small bushings which is an improvement.

https://www.superflex.co.uk/products.php?cat=211

Overall the car is extremely responsive with waaay less body roll and mush in the handling, still quite comfortable.

 

I'll second the KYB all around. Very pleased with them.

 

FYI, for originality, the SportsPack suspension used Boge shocks, which have been superseded by Sachs 311348 (front) and 311347 (rear). However, they are not easy to source.

I found this online too:https://www.jaguarforum.com/showthread.php?t=43634

Richard Mansell: "It was introduced by Jaguar as standard on the 3.6 in Sep 1987 and comprised of 43% uprated front springs, 3% uprated rear springs, uprated Boge shocks all round, increased diameter front anti-roll bar, rear anti-roll bar re- introduced, reduced assistance power steering, stiffer rack bushes and Pirelli P600 235/60 VR tyres on the lattice wheels.”

"The sports seats were originally only available *s part of the SportsPack."

 

I'll 3rd the kybs, had them on 4 different jags XJS, XJ6,XJ12L.. They are pretty comfortable. I tried the Bilsteins. Great shock but expensive and the ride is a bit stiffer, if thats what your after.
Got a complete front end bush kit from british part UK for about $100.0

British Parts <customerservice@britishparts.co.uk>

 

I would go with the KYB. I have Bilstein all round and the left front lasted less than 10,000km before the valving was leaking. Not worth repairing it was cheaper to buy a new damper, still not cheap.

Bushes - definitely keep the lower front wishbone bushes stock IF they need replacing. YOu can go poly in the uppers but unless you are after pinpoint accurate steering stick with stock. I have poly in the rack and uppers and my steering incredibly sharp - no sneeze factor.

If the front springs are the same height when you pull them out leave them. I still have the stock front springs and HD stock ride height rear springs.

 

I get the same combo.

About bushes, I have get poly on the front anti-roll bar, but I prefer the rubber ones for upper and lower wishbones.

 

I want to redo my suspension parts as well. Is there a kit of all the bushings needed to do a complete refresh anywhere? Or if anyone has all part numbers needed

 

take a look here:

https://www.britishparts.co.uk/class...uild-kit-p1759

 

Just a word of caution, for the front bottom wishbone inner fulcrum bushes, you MUST use OEM Metalastic brand bushes. Anything else fails very quickly, and the OEM ones never fail.

 

I did mine. I found that that big bolt on the passenger side cant be removed without pulling off the exhaust pipe. A real PIA.!

 

On the V12 the engine must be supported by a beam across the engine bay and the subframe swung down (swinging on on the front mountings) in order to release the wishbone fulcrum pin.