Hello guys, newbie here, been sifting through a lot of information on the forum - but still need a bit of advice.

In my hello posting I explained how I'm selling my motorcycle and my car to fulfill one of my father's dreams - and gift him a Jaguar. It would be a weekend car. Narrowed everything to three options, all well-maintained - a 4.2 x300, a 3.0 x350 and a gorgeous xj12 HE. All about them, in the above-mentioned post.

The pluses of the first two are obvious - modern cars, still gorgeous, with many of the conveniences of the current era (ahead of their time): parking sensors, heated seats and mirrors, cd player and so on. Downside in both the x300 and the x350 is that taxes in my country are obscene - the 3.0 would be like 500 euros/ 400 gbp/ 600 USD yearly. TRIPLE that for the bigger 4.2.

So i just might decide for the XJ12. The car itself is registered as a historic vehicle, seller seems ok (has a a few other cars as well); it's the third generation, completely restored injection system, problem with the reverse gear cylinder and of course bodywork stuff, rusty arches etc. Upside - tax on this thing is virtually nothing. Downside? Well... he says it's really fuel hungry, 15-25 l/100 km (11-18 mpg). Otherwise, cars seems fine and pampered, will go see it in a couple of weeks.

So here are my questions, and many thanks for your patience:
1. For less hassle, should I opt for the newer models instead of the xj12?
2. Is it possible to install a good LPG system in the XJ12? Anyone did it?

 

Just so you know, the road tax on my 2007 XJ6 Sovereign )X358) 3 litre petrol is £520 per year, (or £10 week ). I would not call your £400 excessive.

Frankly, for the least amount of hassle, your best bet is the 3 litre X350. This has the traditional shape, a reliable engine with 240 PS power, and an aluminium body giving reasonable fuel consumption. Even so, even this car is likely to need attention, but there is lots of stuff on the internet, you don't have to buy parts from Jaguar main agents.

If you buy the XJ12 you'll probably spend 10 times the amount of road tax for the X350 in the first couple of years at least.

 

You don't buy a series 3 XJ for economic reasons...they are not very cheap to get if they are in good condition in Europe, still need a lot of costly work, even if they are in relatively good shape.

BUT: It's the original baby....although the X300/350 XJ's are beautiful and technically A LOT better than the original series, they are still a knock-off in my opinion.
If the body work can be kept to a minimum and the rest of the car is sound, I'd always go for the V12 5.3HE. But that's my personal view....

Slamming in a decent LPG system shouldn't be that much of a problem. I'd opt for and LPI system (liquid propane injection) rather than for a conventional system. The injectors are already there, so the system could be installed quite easily.
Also the HE engine is fit to run unleaded gas (hardened valves and seals), so LPG wouldn't be much of a problem.

 

Many many thanks guys. I tried out the x350 and felt great, two weeks from now I'll hopefully drive the series 3 XJ... I'm literally today for one, tomorrow for the other, can't seem to make up my mind - especially since, as I said in the OP, it's meant to be a gift for my father. Again many thanks for your input - and please don't fret if I come back with more questions ...

 

If the 12 is going to be a weekend car then the fuel economy shouldn’t be too much of an issue, but high usage (on petrol) will soon negate the tax side of things I would have thought.

 

Having owned both the Series III V12 (many, in fact) - and an X350 4.2, I can tell you that there is a clear choice here and it is the X350 if you want to retain your sanity. For an entire year I had both a concours level, low kilometre 1992 V12 Vanden Plas and a 2004 XJ8 (X350) in my garage. I love the beauty of the Series III cars, but somehow the keys to the XJ8 always fell into my hand. It was so much more pleasurable to drive, so much more reliable and so much more comfortable (and those three characteristics are shared by all modern Jaguar's compared to the earlier generations). No comparison.

 

I'm trying to get my head around what a V12 engine bay would look like with a gas system added. Mmmmmm more plumbing :-) but then I am easily scared.

Great thing you are doing for your Dad btw.

 

Guys, can't thank you enough for your input. Waited a while to respond because... well I thought the stories would be worth it - and they are. So for those fond of plot twists and tribulations, here they are:
Went half a country to see the series 3 v12. Amazing car, in the famous gold (or for the opponents of said colour, a runny sick Number Two). I remember reading here somewhere that the view over the steering wheel, with the two headlight bulges, the neverending bonnet AND the leaping cat is the view - yes, indeed, it blew my mind.
...BUT.
I never got to hear ALL the 12 cylinders... poor guy said they usually all fire up (felt like dealing with a WW2 plane really lol) but this happens... just as usually, when the car isn't started for a while - and it hadn't been.
He showed me (a really decent passionate guy actually) the short rubber hoses (you'll forgive my crudeness - they were on the very top of the engine, 3-4 inches short, no idea what they're called in English) of which he said must be changed YEARLY - because the intense heat cooks them (they looked thus). Oh, and the exhaust was agricultural, so to speak, due to a surely undesigned puncture in it.
And when my man wanted to let down the front windows, they refused to do so - much to his amazement and embarrassment.
On top of which he confessed that the car CANNOT run on unleaded gasoline alone, needing a liter-per-liter additive. Oh and the cylinder for the rear gear didn't work.
...bit too much for my 70-year old dad, I suppose, however mechanically inclined he was in his prime (and he was).
In my OP, someone aptly commented the v12 is, quote, "not for the non-spanner person". So true.
... So back to my other aforementioned alternative, the beautiful x350 then!! Way out of my budget but hey.
Only...when i called the guy, "hey this is me, you know... with the Jag etc etc" he said, to my dismay, that he had changed his mind, re-discovered the car precisely when he took ME for a ride to sell it, and sentimental reasons, and so on, and he feels bad etc etc.

So yeah. Back to searching. But yup, gonna be the x300/x350, so I just might politely ask the admin to move this thread to its appropriate section )...

 

I own a beautiful SIII and a magnificent X350. Love them both. Totally different but both unmistakably Jaguar. Good luck in your search.

Jeff