1992 Jaguar XJR-S 6.0

[dme123]

Hi All
Long time reader/lurker here.

Two divorces and unexpected bonus twins have caused an interesting car drought in my life over the last 5 years. Things are looking good again now though, so I felt it was time to scratch the itch.  I've run an X300 4 litre sovereign and an X305 6 litre XJ12 in the past and enjoyed them enormously, both proving to be flawlessly reliable over fairly high mileages. I'd always been put off my the 3 speed auto that all but the last 6 litre XJS had, but only for the same reason that I would find a 3.2 XJ6 so unsatisfactory to own knowing that the 4.0 exists.


I looked at another XJ12 but felt that as a second fun car it was too boring, I considered MX5s, MGBs, a DeLorean (pushing the boat out budget wise!), and then saw mention on PH that another participator in the bargain barge thread would be looking to sell his car soon.  So I bought it.

It's a 1992 XJR-S, which for the non XJS beards was the "tweaked" version produced by JaguarSport in the late 80s and early 90s.  JaguarSport was a shortlived joint venture between TWR and Jaguar.  Engine power was up from ~300bhp in the contemporary 5.3 to 333bhp, which is more than even the later factory 6.0 engine managed.  It has the same three speed slusher as the 5.3 but it is reworked to have quicker shifts and more enthusiastic kickdown.  The big changes relate to the suspension setup, which is a lot more enjoyable to drive quickly than the standard car.  Thing Rover 800 Sterling to Rover 800 Vitesse Sport and you're not far off.  You also get a full Autolux leather interior, none of that ambla curse word here.  Joking aside the leather is incredibly soft and the tarty red carpets and piping are great.

It has some bubbling on the bottoms of the front wings, and the bonnet has been resprayed with a curse word colour match but otherwise appears to be a solid and honest car.  As a previous owner in the JEC said "it's a great usable car, and no garage queen".  No stamped up service book but a wodge of invoices for work done (some of it extremely costly) over the years and it had a service from the PO that included changing all 12 plugs. 

It's pretty quick, although off the line performance is blunted by the 3 speed slusher.  It's outstanding at the all important 60 - 120 sprint though.












and....

[Marc]

That is a thing of beauty. I've had various Jags throughout my driving life, currently a supercharged XJR six cylinder is filling the void, but I must have a V12 at some stage.

How long have you had her?

[dme123]

Only 5 weeks or so. Picked just the right time of year to buy a rust prone, torquey RWD car with no driver aids.

I love the AJ16, but there really is something special about a V12. If you want one get a move on, values for X300 XJ12s seem to be drifting upwards and that is probably the most capable and least needy home the V12 ever had. On paper the performance is very similar to your XJR-6 but it feels very different.

[ian65]

my word, that really is lovely... I sold my xjs 13 years ago and still miss it.

[ChasR]

That looks lovely, and it's looks like it has gone from one good home to another one.

Good to see you off another forum .

[DrSebWilkes]

Amazing car but then I'm biased. I replied to your PM but I'm very sorry for the late reply.

[thechef]

Gorgeous cars  I've had my 4.0 (AJ16) Celebration for over 3 years, such a gorgeous car to look at and fantastic car to drive.

That V12 is one of the best engines - EVER and probably thee best engine of its time, great choice

[dme123]

Think I'm going to need some new speakers...


I finally worked out the issue with the radio and frequent fuses being blown.  The ignition switched +12V was never going live, so some bodger had just spliced the permanentswitched and ignition switched 12V feeds together at the radio loom.

After some investigation of the wiring diagrams it appears that the radio feed passes through the heated seat relay (thanks Jaguar).  I was thrown off because the heated seats worked once so I assumed that relay was OK, but of course they were being powered through the bodgers connection to the permanent 12V.  No wonder that fuse never lasted long.

New relay has both radio and seats working correctly, which has revealed that three of the speakers are in that sort of state and one is completely dead.

[kevins]

must be a BL thing, all the speakers in my range rover looked the same.

[georgeb]

Dec 9, 2016 12:02:40 GMT kevins said:

must be a BL thing, all the speakers in my range rover looked the same.

+1

And still do!

[madwrx]

i remember in the day "performance car" magazine raving about these ,they absolutely loved em.
semi supercar power at the time(the testarossa only had 390) and 30 brake more than bmws engine-lovely car,i,m very jealous lol

[dme123]

Dec 10, 2016 19:41:54 GMT madwrx said:

i remember in the day "performance car" magazine raving about these ,they absolutely loved em.
semi supercar power at the time(the testarossa only had 390) and 30 brake more than bmws engine-lovely car,i,m very jealous lol

Yes it had 333bhp or so from the factory, and it seems to have pretty much exactly the same amount of torque from just over tickover to the redline.  It feels grossly unfair to describe the engine as having no character, but the power delivery really is so linear and the torque curve so flat that there is no sensation of it "coming on cam" or of the power building like with most engines.  I read an interview with Jim Randle the other day and he commented that the V12 is the closest thing to an electric motor that Jaguar have ever made.  Presumably he said that before that electric SUV concept was aired.

The XJR-S is noticeably noisier than a 5.3 V12, both from the sports exhaust and the engine itself.   There were a lot of rather nice mechanical modifications from the standard engine, including Cosworth pistons in matched pairs, along with the Zytek ECU.  Full sequential injection and mapped ignition for 12 cylinders up to 6500RPM was pretty impressive stuff in the late 80s and early 90s.

Interestingly the later factory 6.0 V12 only ever managed 300bhp ish in the XJS and had curse word batch injection and the separate Marelli ignition ECU right until the end.  They managed 318bhp with the distributorless ignition system in the X305 XJ12.

[dme123]

Haven't updated this for ages. We had one minor incident with a small coolant hose splitting, but it was available from Jaguar and only £12. Other than that all has been well. Running average is 13.78MPG, 42p a mile. This means that the 600 miles I've covered have cost £250. I rather enjoy "stretching it's legs" in 1st and 2nd just to hear it howl.

I have also replaced the actual amplifier module inside the Lucas ignition amp, simply because I picked up a brand new one for a song. I've also rebuilt the spare and can keep that handy as they are known to be troublesome.

Some lacquer has peeled off from the scuttle, so I think the car would like me to get on with arranging the bodywork and paintwork attention that it needs.


Friends of the Earth Badge is in the post.


Inside an AB14


Down in the valley


Plenty of legroom. DOn't know why the kids howl so much when I make them get in the back.

[dme123]

The car flew through it's MOT last month with no advisories.

The car had started making a worrying "tap tap tap tap tap" noise at idle, when accelerating, but not at steady speeds. It sounded for all the world like an exhaust manifold blow, and pulling the plug lead off 6B got rid of the noise, but the noise was coming from inside the Vee - the inlet side.

A very helpful user on PH pointed out that these engines have ports down to the exhaust valves to the inlet side of the engine for the US market air injection system and on cars without the system these ports are blocked by the inlet manifold gasket. Mystery solved.

I was short of time so took it to a Jaguar "specialist" in Cardiff who diagnosed a dropped valve (despite me pointing out that I was driving the car at very high speeds just a couple of days before while it was making the noise), curse word around moving injectors around, and then said that they wouldn't actually take the job on in any case. He was adamant it was a dropped valve.

Took it to another mechanic who said it was the head gasket that had gone and the exhaust gasses were blowing up through a head bolt. I realised at this point that I needed to fix this myself.

So a happy afternoon in the sun removing both inlet manifolds revealed an obvious blow on the relevant gasket.



I took the opportunity to replace the bushings on the throttle plate shafts as they'd crumbled away, and on the advice of other XJR-S owners I replaced the 88C thermostats with 82C ones. The car had always run most of the way between N and H on the temperature gauge, which worried me, and it's now bang on the N.

It's running at full strength again now. There is a chap who has been looking for an XJR-S for ages who is very keen to view the car and make me an offer. I'm very torn, it'd be nice to turn a good profit and move it on before it bites me on the bum, and this chap has the space and time to lavish the attention the car deserves. On the other hand it's amazing and I'll never get the chance of any late V12 XJS for the price I paid, let alone an R-S.

Oh an in related news I can confirm that the car will hit the rev limiter in 3rd gear and is still accelerating quite smartly when it gets there. It's undergeared, if it had an overdrive I'm sure it'd be good for 170. The later factory 6 litre got a 4th gear and even with the shorter final drive it should have more headroom at the top end, but it's 30bhp down on the R-S.

[DrSebWilkes]

I know manual conversions for the V12s are pretty popular in the club. Everyone who has them done, or has a factory-standard manual gearbox says the car is an entirely different beast.

Basically the autos were designed for cruising and general wafting - hell even in a XJR-S.