The XJS topic

Author
Discussion

anonymous-user

56 months

Monday 18th May 2020
quotequote all
DP33 said:
Brilliant photo - no idea that the XJ-S was that small! I'll quitely ignore the 750kg weight differential - that makes an XJ-S more dense than any other physical object this side of a black hole...
Well that powertrain is enormously heavy, from memory just the engine and gearbox are circa 350KG. Huge amounts of both coolant, oil, and ATF between them too. It's built on a chassis developed in the 1960s so no computer modelling to know where you need to add reinforcement etc so it's overbuilt (and was built to cope with the mass, torque, and power of that V12), and there is a huge amount of noise supressing material around the car too.

All that mass, and then serious engineering effort to keep unsprung mass down does make for a brilliant ride though!

DP33

183 posts

128 months

Monday 18th May 2020
quotequote all
stickleback123 said:
DP33 said:
Brilliant photo - no idea that the XJ-S was that small! I'll quitely ignore the 750kg weight differential - that makes an XJ-S more dense than any other physical object this side of a black hole...
Well that powertrain is enormously heavy, from memory just the engine and gearbox are circa 350KG. Huge amounts of both coolant, oil, and ATF between them too. It's built on a chassis developed in the 1960s so no computer modelling to know where you need to add reinforcement etc so it's overbuilt (and was built to cope with the mass, torque, and power of that V12), and there is a huge amount of noise supressing material around the car too.

All that mass, and then serious engineering effort to keep unsprung mass down does make for a brilliant ride though!
Couldn't agree more - my 3.6 rides much better than my daily driver (a 640d - running on 19' RFTs) - it just shrugs off pot holes and broken Tarmac that really disturb the BMW. Throw in the absence of road noise and I'm not sure how much progress there's really been in the last 30-odd years.



Simpo Two

85,883 posts

267 months

Tuesday 19th May 2020
quotequote all
DP33 said:
Couldn't agree more - my 3.6 rides much better than my daily driver (a 640d - running on 19' RFTs) - it just shrugs off pot holes and broken Tarmac that really disturb the BMW. Throw in the absence of road noise and I'm not sure how much progress there's really been in the last 30-odd years.
Bingo. 'Comfort', which was once something desirable, seems to have been forgotten. It's like everyone replacing their sofas with wooden benches and saying 'Ooh this is sporty!'

Mark-C

5,248 posts

207 months

Tuesday 19th May 2020
quotequote all
Simpo Two said:
DP33 said:
Couldn't agree more - my 3.6 rides much better than my daily driver (a 640d - running on 19' RFTs) - it just shrugs off pot holes and broken Tarmac that really disturb the BMW. Throw in the absence of road noise and I'm not sure how much progress there's really been in the last 30-odd years.
Bingo. 'Comfort', which was once something desirable, seems to have been forgotten. It's like everyone replacing their sofas with wooden benches and saying 'Ooh this is sporty!'
Mrs-C drives a Kia Soul that spends all of it's time on crappy city roads and is on 18" wheels and 45 profile tyres - madness!

anonymous-user

56 months

Tuesday 19th May 2020
quotequote all
Mark-C said:
Mrs-C drives a Kia Soul that spends all of it's time on crappy city roads and is on 18" wheels and 45 profile tyres - madness!
Ex Mrs Stickleback picked an XC60 about 4 years ago to replace a much loved V70 T5. It's "SE Lux" spec with 18" wheels but massive sidewalls due to a 235/60 tyre (14cm of sidewall!) and it still rides like absolute crap because the suspension has to be really stiff to give it that "car like drive" that stops ex wives from putting tall cars on their roof.

My kids find the way my MX5 jiggles along the road less uncomfortable than the XC60 crashing over everything and think my X350 (which I think rides really quite poorly for a car of its type) is a hovercraft.

My XJRS had a much more focussed suspension setup than a regular XJS but the ride was still absolutely wonderful, while still being capable of rapid progress on a good road. It was very secure and inspired a lot of confidence even on poor surfaces.

GiveItSomeWellie

3,013 posts

198 months

Tuesday 19th May 2020
quotequote all
Got some pictures of the XJR-s next to the old mans latest purchase. RS Grandfather and Grandson smile

Very, very different to look at (and to listen to), but they share more in common than you might think when you drive them.

















Not much to see on the new one with the engine cover off!

While we're on the subject of dimensions, they are both remarkably similar; The XK is 19kg heavier, 20mm longer, 10mm wider.

dinkel

Original Poster:

27,016 posts

260 months

Tuesday 19th May 2020
quotequote all
Fantastic to compare these 2.

craigjm

18,133 posts

202 months

Tuesday 19th May 2020
quotequote all
The original XK was based on the XJS of course and they kept the proportions similarish on the new one to create a familiarity. One thing it does share for sure is the useless back seat hehe

GiveItSomeWellie

3,013 posts

198 months

Tuesday 19th May 2020
quotequote all
craigjm said:
The original XK was based on the XJS of course and they kept the proportions similarish on the new one to create a familiarity. One thing it does share for sure is the useless back seat hehe
I was going to mention this hehe In saying that, the XJR-s definitely has more headroom in the back, Dad is 6ft tall and sat along the back seat on the way to collect the XK.. I can't imagine he'd even consider getting into the XK!

Seeing as though this year looks to be a write off, I've started plans to take the XJR-s down to the Millie Miglia and back via the Nurburgring for next year.. It just seems so far away at the moment frown

DP33

183 posts

128 months

Friday 22nd May 2020
quotequote all
GiveItSomeWellie said:
Got some pictures of the XJR-s next to the old mans latest purchase. RS Grandfather and Grandson smile

Very, very different to look at (and to listen to), but they share more in common than you might think when you drive them.

















Not much to see on the new one with the engine cover off!

While we're on the subject of dimensions, they are both remarkably similar; The XK is 19kg heavier, 20mm longer, 10mm wider.
Great shots and wonderful to see the two cars together like that. But did I read that right? Is the aluminium XK really 20kgs heavier than the XJR-S - Surely not? I also can't believe that it's only 1cm wider. The XJ-S cabin just feels so narrow while the XKs doesn't...



DP33

183 posts

128 months

Friday 22nd May 2020
quotequote all
Mark-C said:
Simpo Two said:
DP33 said:
Couldn't agree more - my 3.6 rides much better than my daily driver (a 640d - running on 19' RFTs) - it just shrugs off pot holes and broken Tarmac that really disturb the BMW. Throw in the absence of road noise and I'm not sure how much progress there's really been in the last 30-odd years.
Bingo. 'Comfort', which was once something desirable, seems to have been forgotten. It's like everyone replacing their sofas with wooden benches and saying 'Ooh this is sporty!'
Mrs-C drives a Kia Soul that spends all of it's time on crappy city roads and is on 18" wheels and 45 profile tyres - madness!
The other thing I'd throw into the mix are seats. Those in the XJ-S are incredibly comfortable. You forget how soft / supportive seats can be (remember how 80's Renault seats used to swallow you whole) when you smoke around in German kit all day. In all fairness if you read a contemporary road test of a BMW or Mercedes from the 80's the mags used to say that the seats were too hard in period, so I suppose that at least the Germans are consistent...

a8hex

5,830 posts

225 months

Saturday 23rd May 2020
quotequote all
DP33 said:
Great shots and wonderful to see the two cars together like that. But did I read that right? Is the aluminium XK really 20kgs heavier than the XJR-S - Surely not? I also can't believe that it's only 1cm wider. The XJ-S cabin just feels so narrow while the XKs doesn't...
Like you I'd have thought the X150 was rather wider too, I was a sad enough git to look at the figures on Wiki and they claim the width are 70.6" and 74.5". The XJ-S makes up for it in length though, being 3" longer.
They don't give weights for the XJ-S and only one weight for the X150 and the XK and XKR are going to be somewhat different.

anonymous-user

56 months

Saturday 23rd May 2020
quotequote all
Weights and dimensions off the internet are all over the place; brochure figures seem to be the most sensible ones to use if you can find them. I'd be absolutey floored if the all aluminium XKR with 2/3rds the engine is a similar weight to a V12 XJS; brochure figure for my XJRS was 1825KG and when I went on a weighbridge at a clients site it was nearly 2000KG with me in the car, a full tank, and a bootful of crap.

A 2003 X350 with the NASP V8 is 1650KG and I'd expect the X150 to be lighter than that but probably not by much.

a8hex

5,830 posts

225 months

Saturday 23rd May 2020
quotequote all
Here's the details for the XKR from the owners manual




Which confirms your suspicion that the XKR is lighter.

The XJS launch brochure is available at http://www.jag-lovers.org/brochures/xjs_launch_hil...
This doesn't show mirrors and has a width of 70.60"
The final XJS brochure is at http://www.jag-lovers.org/brochures/xjs_3-96.html
This shows the width with and without the mirrors, with it's 74.1 so even mirrors out the XJS is narrower than the XKR (X150) with the mirrors folded.
I was surprised the difference between the front and rear track of the the XKR wasn't larger, Those rear arches really seem much wider when I'm reversing mine.

DP33

183 posts

128 months

Saturday 23rd May 2020
quotequote all
a8hex said:
Like you I'd have thought the X150 was rather wider too, I was a sad enough git to look at the figures on Wiki and they claim the width are 70.6" and 74.5". The XJ-S makes up for it in length though, being 3" longer.
They don't give weights for the XJ-S and only one weight for the X150 and the XK and XKR are going to be somewhat different.
I think I've got the monopoly on being truly sad - just checked the original 1982 HE road test in Autocar and the "weight as tested" was 1921kg! Saying that it still did 0-60 in 6.5 seconds and topped out at 153mph one way and 157 the other - so clearly that was one very fit V12...

anonymous-user

56 months

Saturday 23rd May 2020
quotequote all
DP33 said:
I think I've got the monopoly on being truly sad - just checked the original 1982 HE road test in Autocar and the "weight as tested" was 1921kg! Saying that it still did 0-60 in 6.5 seconds and topped out at 153mph one way and 157 the other - so clearly that was one very fit V12...
Through a three speed slusher no less!! My XJRS would hit the rev limiter in 3rd.

DP33

183 posts

128 months

Sunday 24th May 2020
quotequote all
stickleback123 said:
DP33 said:
I think I've got the monopoly on being truly sad - just checked the original 1982 HE road test in Autocar and the "weight as tested" was 1921kg! Saying that it still did 0-60 in 6.5 seconds and topped out at 153mph one way and 157 the other - so clearly that was one very fit V12...
Through a three speed slusher no less!! My XJRS would hit the rev limiter in 3rd.
Always suspected that all Jag V12s were not created equal - my Old Man's first HE (''84 on the A) was head and shoulders quicker than the 2 later cars he had. Unfortunately that first car did rather disgrace itself by rupturing a fuel line and burning out when it was just 9 months old....

anonymous-user

56 months

Monday 25th May 2020
quotequote all
DP33 said:
Always suspected that all Jag V12s were not created equal - my Old Man's first HE (''84 on the A) was head and shoulders quicker than the 2 later cars he had. Unfortunately that first car did rather disgrace itself by rupturing a fuel line and burning out when it was just 9 months old....
It's very possible that the manufacturing tolerance at Jaguar itself and all their component suppliers were loose enough to make a big difference, they were hardly a paragon of fine manufacturing. Also quite possible that they continued using worn tooling long past the point where a proper company would have changed it! I remember reading that for the factory 6 litre engines they significantly tightened up the specifications, presumably under the guiding hand of Ford.

DP33

183 posts

128 months

Monday 25th May 2020
quotequote all
stickleback123 said:
It's very possible that the manufacturing tolerance at Jaguar itself and all their component suppliers were loose enough to make a big difference, they were hardly a paragon of fine manufacturing. Also quite possible that they continued using worn tooling long past the point where a proper company would have changed it! I remember reading that for the factory 6 litre engines they significantly tightened up the specifications, presumably under the guiding hand of Ford.
I suspected that was the case and reading around the subject absolutely supports your point. The post-Ford era cars were a lot better engineered; from body-in-White through to powertrain and they weren't built on worn out tooling. For example the seam width on the boot aperture in my '88 car are about 4-6mm different side to side - but what can you expect when those presses had done 13 years worth of work already?

Simpo Two

85,883 posts

267 months

Monday 25th May 2020
quotequote all
DP33 said:
The post-Ford era cars were a lot better engineered; from body-in-White through to powertrain...
That's two threads that 'body in white' has come up. Had a google but none the wiser. What does it mean?