1992 Jaguar XJR-S

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Discussion

larrylamb11

585 posts

251 months

Wednesday 22nd March 2017
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J4CKO said:
That reminds me of the toy XJS I bought and cherished when I was seven, same colour, they were the car for 1970s/80s kids,like this, can remember buying it in Torquay on holiday and getting it out of the box on the steps of the toy shop.

https://www.youtube.com/watch?v=CeA7_I0xChA
I had one of these too... and also cherished it. It was often the 'scrap yard owners car' for me when playing toy cars back then... proudly sweeping into my diorama constructed from stacks of more battered matchbox cars piled 4 or 5 high in homage to the rare but intensely fascinating trips to the scrap yard accompanying my father as a small boy..... ahhh, happy memories!
I have recently retrieved my old toy cars from a extended languish in a loft and passed them all onto my own small boy, including my once cherished and still handsome deep red XJS. His indoctrination into old cars has begun....

anonymous-user

Original Poster:

54 months

Thursday 6th April 2017
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Started getting the inlets off today. Not particularly difficult but I started late and the light was fading so I'll finish it tomorrow.

The bodger has been here before, as witnessed by half the injector plugs already being broken around the clips and the three missing serrated Jaguar washers having been replaced with conventional springy locking washers around the blowing cylinder. None of the nuts on the inlet manifold were not particularly tight either.

Only bits remaining to be disconnected are the fuel lines and then myself and an able helper will lift of the inlets, airboxes, and fuel rails all in one. I'll also add "replace injector connectors" to the non urgent list of jobs. I've spoken to a chap who has done this by poking the pins out of the broken connectors to put back into new ones and it was a fiddly three hour job.

anonymous-user

Original Poster:

54 months

Saturday 8th April 2017
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Job done!



Thank you very much Mr. Hooker, you were absolutely correct and it was blowing at the inlet manifold from the air injection port to the exhaust valve, it was obvious once the gasket was off. The whole job was really very straightforward if time consuming simply because there are so many bolts and so on compared to a smaller engine. So much for the dropped valve one Jaguar "specialist" diagnosed and the other two mechanics too scared to even touch it.

I took the opportunity to replace the throttle shaft bushing things on both inlets, changed it from 88C thermostats to 82C thermostats as recommended by fellow XJR-S owners, and remove the slack in the cruise control linkage.

It sounds as it should again now, and the temperature needle is now only very slightly above the middle of the dial rather than worryingly close to the 3rd dash.

One lesson (re)learned: take off the petrol cap otherwise there is enough pressure to ensure a steady drip drip drip of fuel from the disconnected fuel supply.

I've run it up to temperature and it's cooling down now ready for a coolant level check. I'll take it for a 2 hour trip and then check the torque on the inlet manifold bolts and then do the same in a little while as it is a thick gasket and looks like it might settle a fair bit.

toastyhamster

1,664 posts

96 months

Saturday 8th April 2017
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Good work. Back in the day I used to work for a garage specialising in these, I mostly did bodywork (never ending!), we did a few conversions to cabriolets, rebuilt a few of the v12s, fitted some TWR kits. Never really had many HE's in though.

Always fancied one, despite me knowing how painful it could be.

anonymous-user

Original Poster:

54 months

Thursday 13th April 2017
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Car is fit and well, a slight nip back up the the specified torque required after a 200 mile (£66 of fuel) run.

I have also confirmed that the car is in excellent health and will hit the rev limiter in 3rd.

toastyhamster said:
Good work. Back in the day I used to work for a garage specialising in these, I mostly did bodywork (never ending!), we did a few conversions to cabriolets, rebuilt a few of the v12s, fitted some TWR kits. Never really had many HE's in though.

Always fancied one, despite me knowing how painful it could be.
It is addictive. I think the later cars, particularly the late 6 litre ones, are very much less needy than the pre HE and early HE examples. If you want one do it quickly as prices seem to be getting to the point where you can't buy and run one on a whim. The six cylinder cars are still available quite cheaply as the auction linked here last month demonstrates, but I think if you've experienced the V12 they are always going to feel a bit lacking.

Edited by dme123 on Thursday 13th April 12:46

melhookv12

958 posts

174 months

Thursday 13th April 2017
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I'm glad to be of assistance.
Now all you need to do is buy my big valve heads and 7.0litre Lister bottom end. Then you'll have a real v12!!

anonymous-user

Original Poster:

54 months

Thursday 13th April 2017
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melhookv12 said:
I'm glad to be of assistance.
Now all you need to do is buy my big valve heads and 7.0litre Lister bottom end. Then you'll have a real v12!!
I think I'd want to get rid of the three speed slushpump too in that case! You seem to be a man in the know with the V12, maybe you can answer something that I've been wondering: considering the changes made to the XJR-S (longer stroke, cold air inlet, different valves, cosworth pistons, bespoke and far more sophisticated ECU) why was the power increase over the 5.3 so modest?

craigjm

17,956 posts

200 months

Thursday 13th April 2017
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dme123 said:
melhookv12 said:
I'm glad to be of assistance.
Now all you need to do is buy my big valve heads and 7.0litre Lister bottom end. Then you'll have a real v12!!
I think I'd want to get rid of the three speed slushpump too in that case! You seem to be a man in the know with the V12, maybe you can answer something that I've been wondering: considering the changes made to the XJR-S (longer stroke, cold air inlet, different valves, cosworth pistons, bespoke and far more sophisticated ECU) why was the power increase over the 5.3 so modest?
I have the same engine in my XJC and my understanding was that all the difference is was a longer stoke and a wizzy ECU left over from racing? Are you sure it's got different valves and pistons? A link to the info would be great

anonymous-user

Original Poster:

54 months

Thursday 13th April 2017
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craigjm said:
I have the same engine in my XJC and my understanding was that all the difference is was a longer stoke and a wizzy ECU left over from racing? Are you sure it's got different valves and pistons? A link to the info would be great
I'll e-mail you the JaguarSport docs I can share on the XJR-S. Some are protected PDFs that I need their annoying software to open but what I do have will give you the gist.

ETA - Sent. It has a full list of parts that are different and their SPC part codes. Camshafts are standard, valves are unique, parts listing for those here

https://www.jaguarclassicparts.com/uk/jaguar-xjs-v...

One of the other documents states that they are forged alloy Cosworth pistons supplied in balanced matched sets, and the crank is forged steel. Gudgeon pins material is uprated, the crankshaft undershiled is different

The Zytek system has a 24 speed x 16 load map but they count position zero so it has 425 mapped positions. It has cut off on overrun above 2000rpm and reinstates at 1900rpm once coolant is over 75C.

19% increases in torque and power over a 1992 MY 5.3. If you have the pre facelift 6 litre engine then the ECU is open loop only and has no lambda sensors. You get less power and torque from that.

The transmission was modified too so that it shifts more quickly.

Edited by dme123 on Thursday 13th April 16:36

melhookv12

958 posts

174 months

Thursday 13th April 2017
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I didn't know the valves were different. Bottom end yes as you say cosworth bits.
In my view jaguar never exploited the v12. There are a few racing guys that have noticed a big difference by going to a modern ecu ( emerald ) and two separate coil packs like the late jaguar ( foRd 6.0 litre).

Breathing is a big thing, cold air, larger throttles, and exhaust manifolds. I have heard different figures ranging from 20-50 bhp with the above mods. I had a v12 on webbers, race cams and tubular manifolds that gave circa 400bhp. That was 10 years ago.

Changing to a manual gearbox transforms the car, it wakes it up, our first v12 would nearly hit 60mph in first gear ! It just depends what you want and how much you want to spend.

Someone is making/ selling group A inlet manifolds but they aren't cheap. But if you want power on injection they are a must.

I have tubular manifolds that are for sale. I've defected to supercharged v8. A long project to fit it to my xjs. It's a more modern, lighter compact engine.

I only found out my car was one of the factory manual cars when I stripped the engine bay to reveal the chassis number.

anonymous-user

Original Poster:

54 months

Thursday 13th April 2017
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melhookv12 said:
I didn't know the valves were different. Bottom end yes as you say cosworth bits.
In my view jaguar never exploited the v12. There are a few racing guys that have noticed a big difference by going to a modern ecu ( emerald ) and two separate coil packs like the late jaguar ( foRd 6.0 litre).

Breathing is a big thing, cold air, larger throttles, and exhaust manifolds. I have heard different figures ranging from 20-50 bhp with the above mods. I had a v12 on webbers, race cams and tubular manifolds that gave circa 400bhp. That was 10 years ago.

Changing to a manual gearbox transforms the car, it wakes it up, our first v12 would nearly hit 60mph in first gear ! It just depends what you want and how much you want to spend.

Someone is making/ selling group A inlet manifolds but they aren't cheap. But if you want power on injection they are a must.

I have tubular manifolds that are for sale. I've defected to supercharged v8. A long project to fit it to my xjs. It's a more modern, lighter compact engine.

I only found out my car was one of the factory manual cars when I stripped the engine bay to reveal the chassis number.
I can't see why the valves would be different, but they are listed with separate SPE part numbers with Jaguar.

I was surprised that in the XJS the factory 6.0 only made 300bhp to the 333bhp in the XJR-S, although I believe right up to the end it used batch injection and a separate ignition system in the XJS and never got the integrated engine management system and distributorless ignition that my X300 XJ12 had.

It would be nice to start to get real power out of the V12, but I suspect it would be an extremely expensive journey as you say!

craigjm

17,956 posts

200 months

Thursday 13th April 2017
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im gonna fit an emerald ecu to mine and coil packs if i can
Love the idea of a manual but i love the relaxed cruise of an auto. Found a four speed box solution, shame cant fit anything more modern.

anonymous-user

Original Poster:

54 months

Monday 17th April 2017
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Covered about 500 miles in the last week or so, lots of motorway work and averaged 18.4mpg or so which I think is very good. It seems to get exactly the same fuel economy at every speed between 50 and 90mph. My old XJ6 was like that, it did 20mpg if you drove it like you wanted to and 22mpg if you drove like an absolute twinkle toes.

It really is a delightful way to travel, for all the climate control system is primitive it does seem to be effective at keeping the air in the cabin fresh and at an even temperature. It's as comfortable as a modern coupe with sporting pretensions, although there is more wind and road noise.

SebringMan

1,773 posts

186 months

Thursday 20th April 2017
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I saw this car outside Warwick Sports the other day ; I am there most weeks during the evenings. My M3 was parked around a row away from it. It looked great at night time smile.

Initially I was wondering if it was an XJR-S until I checked the no. plate. It looks fantastic.

anonymous-user

Original Poster:

54 months

Monday 24th April 2017
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SebringMan said:
I saw this car outside Warwick Sports the other day ; I am there most weeks during the evenings. My M3 was parked around a row away from it. It looked great at night time smile.

Initially I was wondering if it was an XJR-S until I checked the no. plate. It looks fantastic.
Thank you, it's nice to know the car was appreciated by someone else! It does look good at night, from a bit of a distance away.

Which brings me on to the latest news. I've sold it. A chap from the XJR-S nerd group had a friend who had been looking for one for ages. I took the car up to see them, which gave me the opportunity to get it connected to the only functioning Zytek diagnostic computer and have it looked over by two impressively beardy XJS/XJR-S people.

The consensus was that the trim was in fantastic condition, mechanically it was superb and drove well, but they found all sorts of rust in the sills and above the exhaust boxes that I didn't know about. As in "put your hand in here and you can poke a hole through it". Sobering stuff. Full credit to the chap who was looking to buy, he stood by the offer made before the rust was revealed and a deal was done.

It's going to benefit from a cost and time no issue restoration now, which is something that in truth I was not in a position to do. I've had six fantastic months with the car and covered all my costs so I consider that a good result. Now to find something completely different...


SebringMan

1,773 posts

186 months

Monday 24th April 2017
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That is a shame but sometimes it is a the right thing to do. Finding the right peiple for it to go to under the correct circumstances is trickier. It sounds however that this did happen which is good smile.

craigjm

17,956 posts

200 months

Tuesday 25th April 2017
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So where next?

Bill Whiteside

9 posts

78 months

Tuesday 10th November 2020
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I own a 1987 TWR buit 6.4 XJS with Zutek ECU, I have built hardware which connects to the ECU and i am able to download the ECU code using a 1992 base file!! I am trying to reverse engineer the software but am needing another version of the base file for comparisons. Has anyone got any software information or another file anything would help but closer to 1987/8 would really help me.

anonymous-user

Original Poster:

54 months

Tuesday 10th November 2020
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Bill Whiteside said:
I own a 1987 TWR buit 6.4 XJS with Zutek ECU, I have built hardware which connects to the ECU and i am able to download the ECU code using a 1992 base file!! I am trying to reverse engineer the software but am needing another version of the base file for comparisons. Has anyone got any software information or another file anything would help but closer to 1987/8 would really help me.
I know a chap who has the Zytek interface but having just spoken to him he said he thinks he's chatted to you in the past and hasn't been able to help, which is a shame. All I can do is wish you good luck, sadly.

Dave3166

1,770 posts

126 months

Tuesday 10th November 2020
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My father brought one of the limited edition Jaguar XJR-S when they came out, to celebrate the Jaguar’s winning LeMans 24hr’s.
I believe they came in 1st, 2nd & 3rd.
They were all finished in a metallic grey colour from what I can recall.
People that brought them at the time were invited to silverstone to have rides in the winning jags around silverstone.
Me & my father had rides with Jan Lammers.
Absolutely fantastic day.