Teach me about the Jaguar XJS's V12 Engine

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Soldato
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Im looking at an XJS at the moment made in 1978 :D

Im wondering about the egine it has sitting in it?
From what ive found so far it seems to be the Origanal 5.3L engine and not HE engine.

So could someone please tell me all about the engine and the car its sitting in? :)
 
its always pub talk to get one that leaks oil, stops some of the rust.

Doubt theres any truth in it though
 
Oil leaks are common, my dad had the XJ 5.3 but it was the HE. Dual fuel tanks can remember when I was 13/14 being £80 quid to fill up so todays prices would prob bankrupt you :D. It did suffer from oil leaks, but nothing major. His is currently in a bodyshop being restored month by month back to tip top condition. I remember once when we drove to France the alternator breaking but apart from that nothing went wrong with it, but being in the motor trade he meticulously looked after it and self serviced.
 
The 5.3 is crippling to run. It makes about 230BHP upwards depending on what condition it's in and what it's fitted in, with torque peaking at about 300ft.lb. You'll average about 20-22 on the motorway and about 10 around town - less if it's not in top notch condition.

They're expensive to run, can be very tricky to maintain if you don't know what you're doing or have a bad one and a fortune to repair if they go wrong in any major way.

The XJSs are fairly solid but are total rust traps.

A nice one is about 1500-2000 (with immaculate ones being around 3k) with T&T, so bear that in mind when looking at them - sheddy ones aren't worth anything as they're extortionate to put back on the road - hence why you can pick up rusty, tatty T&Td ones for 800 quid.

The 80s 3.6 straight six is a much nicer, more streetable powerplant than the V12 and isn't really far off in terms of performance or cruising ability either. You can pick up a very clean one of those for around a grand...
 
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The car ive been watching doesnt seem to have much/any rust at all so thats not too much of a problem.
We dont have such a bad rusting problem down here, well nothing compared to what you have up there

Are the Oil leaks much concern of these engines and take much to fix? or are not too much of a problem?
If i do buy it(and not go holidaying later in the year with the GF) then it will be more of a weekend car so the amount of petrol it uses wont bother me at all :D
The owner of the car said he gets 6kms per litre if its not driven too hard :p

I only want the V12, the 6s dont really interest me. I just would love to have a V12 on the drive :o
 
Don't bother with the pre-HE ones, they drink more fuel than the HE and put out less power.

On my HE I had the center exhaust boxes removed (replaced with straight through pipes). These boxes are only really for noise reduction, so if you don't mind a little bit more noise when pushing it, removal gets you a little bit more power and a lot better fuel consumption. My HE was getting ~16-19mpg around town and 25-30mpg on a the motorway without the center boxes.

Not too hard of an engine to work on yourself, just looks scary. I even managed to replace the gearbox on my own with it up on wheel ramps. There are a few gotchas though. Changing the spark plugs is awkward - one of them can't even be removed without removing the air-con pump.

Quick power increases can be had by a) the exhaust mod above and b) removing / enlarging the air intake trumpets as they are quite restrictive. Again, they are only really there to make things quiter.
 
didn't they have one of these cars on top gear a few years ago where they suggested taking it to a modding company that pretty much fixes it up so they dont break so often? tho i guess you would have to drive it a lot to make it worth the money.
 
The noise of a V12 would be WIN so loadness wont bother me :D
And like i said petrol consumpion wouldnt bother me because i have the camry for day driving. Pluss we only pay 120cents-130cents for petrol at the moment :cool:

Not sure if the police would agree, just as long as i didnt have to sit there with a constant drone that hardly changes tone like some cars ive been in do. :)

Heres a picture of the one im looking at.
JagXJS.jpg


Its only $300-$400 Third party fire theift

/dirty thoughts :o
 
The problem with one of these as a 'toy' is that because they are susceptible to many niggling electrical & mechanical faults (assuming you're buying relatively cheap ones), that it won't be any fun at all because every time you drive it you'll be thinking "what's that light.......what's that new noise...why don't my windows work" and so on.

There's not really much you can do with them either, unless you want to ruin any resale or the car itself.

They're not fantastic fun to drive either - they're big tourers and whilst relatively quick in a straight line, not that engaging to chuck about :)
 
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