looking at getting a 1990 xj12 vanden plas (sp?), just had some questions. I am newly mented to these cars. does anyone know rear end ratios in these cars? does this car still have the rear brakes inward (on the rear diff) or are they outward? what is the rough weight of the v12 engine? if it is more plausible for maintenance sake, I may choose to attempt a small block chevy transplant. Anybody know of anybody that has done something like this. BTW, the car in question has had an electrical fire under the passenger side dash so this will probably help in decision making. I do not know the extent of the wire melt down but will know more soon.

 

You want the section titled "XJ6 XJ12 to 1987" even though you have a 1990. Don't ask :-)

You have a 2.88 limited slip diff

Inboard rear brakes

Not sure of the engine weight... 600 pounds?

Cheers
DD

 

thank you Doug.... will do and will not ask.

 

Thanks Doug , I moved the thread into the proper area

 

according to the specs I read on mine, the V12 weighs around 700 lbs.

 

Hi Velder:

Weclome to the forum's and if this can be seen as helpful advice, PLEASE DO NOT even consider a chev engine. If that is even an option do not buy the car.
A V-12 engine is a rock solid engine that will give you 500.000 kilometres if it is looked after. If it is NOT looked after and provided it is never overheated, it may only give you 3-400 K. That fire under the dash will not be aided nor gotten around by a chev engine.

If it runs it is always better to maintain the original engine.
There are dozens of reasons to not do it and maybe two legit reasons to actually do it, although legitimacy is no less grating.

Having said that you have a fairly rare car in 1990 NO XJ-12's were imported directly to the USA, and actual production numbers were fairly low. However these cars don't seem to be aware of their status as the feel just as free to rust as the seventies versions did...and do. They also don't have a really high value yet.
So, "Krown" it, love it, service it well, especially the cooling system and don't over heat it. Also don't ever bother with a full major tune up or try adjusting the chains. The car will run for a long time very well even without this. The distributor can always be seen to during a tune up, and indeed this and the plugs are the most important. GFollowing this will save you some money and shock as the price of a full tune up on a V-12 will cause high blood pressure. So this helps a lot with the cost of ownership.

Sorry if it seems like I "went off" on the conversion plan, I admit to being sensitive about it. It is just that I have noticed a number of connecting issues to every conversion related to the type of person who does them. They are never Jaguar lovers, they just maybe dig the shape "wow its a georgeous car" with no thought to the actual engineering and the complete car.
To me its kind of like a guy who wants to sleep with your daughter just cause she's pretty and then guts her, Its just asking for some trouble from her father. (OK, OK, LOL)

Most of these converted cars eventually end up in the scrap heap (@#%$#&^*) or if they end up on the road they are never exactly right, and the cost? Usually WAY more than just fixing the engine.
Economically it is a no where fast way to go.

So Velder, after having embarrassed myself by all this ranting I really should say, unless you really know something about Jag's I would stay away from any car thats had a fire unless it is a sixties or older model as they get way complicated.
Now is it a fire? Or was it just smoking and melted a few wires? My opinon should be watered down according to your skill level coupled with the actual condition of the car and reason for the fire. You are the one who really will know what you can do.

Thanks for reading this and, wow, I promise I am not always like this.
Usually a lot more friendly.

Cheers,
JustV12

 

I welcome all feedback. I am new here and I probably have limited access but I will try to post some pictures of the kitty somewhere so you who know what it is you are looking at can take a look and tell me what you figure. I have looked into the car and I have not seen any smoke evidence at all so I do believe that it was a wiring meltaroo (the guy had tried to put in an after market stereo and I think that is what took a dump). I learned just today that the car indeed was started and drove under its own power back home (about a 20 mile trip). The car has sat outside for the last two years with the bonnet open about 4" (we get some hum dingers of winters up here). I am not in a position to attempt a full on rebuild as I have three kiddos and mortgage. At the asking price I think I would be a wierdo to not pick it up. The guy wants a $100. Yes, thats right one hundred bucks. I will probably try to unload it either the way it sits or yank the engine and trans and see if there is any interest. I am a dreamer with some fun ideas. If no one wants her or the pieces of her, than I was thinking it would be fun to build a scale tank car like Jay Leno's blastolene. Albeit it would not even be close to the magnitude of that car, it would still be fun to have a v12 tanker. More realistically I would like to yank the rear end and build a trike, but that all takes money.

 

When looking from the front of this car towards the rear differential, what direction does the drive shaft turn? Clockwise or counter clockwise?

 

Although I am of the same mindset as JustV12, I have to disagree with him in one respect. I picked up a perfectly good, complete V12 for with only 49,000 miles on it for just $100 because someone wanted to drop a Chevy 305 into their XJS. So if they want to butcher their car for my benefit, who am I to stop or judge them?

 

LOL, exactly Jamey:

I once picked up a V-12 engine from a guy in Ohio, because he couldn't find anyone in Geneva to fix the V-12 properly. So out of frustration he did the swap, and I benefited.

However, from an owners persepctive if the car NEEDS an engine swap it makes a bad investment. Especially since these cars are worth a maximum of 5 grand right now in really nice shape.
I would stay away from a car like that because the engine swap will cost more than the car is worth and lessen the value of the finished car. That was really my point there. Benefit from someone elses bad move, don't create one for others.

Now, if you already OWN the car...and you explode the V-12 engine...and you love the car...and it is really in decent shape otherwise...and you CAN'T find a good V-12 replacement...ANYWHERE...then that is one of the legitimate (but still grating) reasons to put in the chev engine.

So believe me, I do get it, it's just that the conversions kill the values, and I have yet to see one done really well and they seem to NEVER be properly finished, and it seems to be the sport of smug *%#^**## 's
and other low rent types who just do not get what a Jaguar is. In short, most of them just ain't our people.

Did I say this already? It is very much like some slimey guy telling you he wants your daughter for sex because she looks good, and cares nothing for her personality or who she is.

Ok am I taking this WAY too seriously?? Yah think??
This may be a good place for an "LOL" just to lighten things up a bit.
So LOL everyone!!
Besides, my brother in Florida may be reading this and he already thinks I am way too bent on Jags.
Never mind HIS increasing Jag count.

Anyway on the lighter side, I met one guy, that is to say ONE GUY, out of 15 conversions that I have had the sadness to witness first hand, ONE GUY!!!! That was actually a Jag nut and who did the swap for legit reasons. Even HE vowed that as soon as he had a reasonable Jag V-12 engine, he would return it to it's original state. Out of countless conversions offered for sale all over this great continent, from California to Newfoundland, 1 guy.

I exhaust my self with this stuff...really.
I need to go lay down now.

JustV12.
(breathing very deeply)

Come on people laugh with me here...it's all we can do.

BIG P.S. here, this OP was offered the car for $100 dollars. That changes the equation significantly.
If that engine still turns freely it is salvagable.
I would pay $100 dollars for a 1990 XJ-12 in a heartbeat, running or not.
However we don't need more "lumps"

Thank you for being amused at my rants.

JV12

 

Hello all, I managed to grab the camera and grab some shots of the old girl. Please go to my garage to see the pictures. It obviously needs some sheet metal (pass. front door, pass. front fender, hood), and I am not sure of the engines ability to run seeing as it sat with the hood up about 4-6 inches through two of out famous Manitoba winters. I do know that it was not parked because of any engine failure or nothing like that, it had an under the dash wiring fire (that looks more like a "melt down" than a fire to me as evidenced by the lack of smoke). Does this qualify as rare enough to fix for $ gain? or part it out? or make a really cool coffee table with the engine block? or???

 

In MINT condition that model is worth $$$ to the right buyer.

I'll be candid....in the condition it's in it's pretty much just another used up old Jag. I can envision cubic money being spent to bring it back to the level where it would be worth big bucks.

It's really a shame, though, as a Ser III V12 is one of the most desirable models.

Others will chime in.

Cheers
DD

 

does anyone know what the weight of the block alone is (stripped of all bolt ons with only the liners left in)? I do not want to be sacrilegious but it may be that I'll yank the engine and make a coffee table out of the block. As much as I know the engine worked fine when she was parked.

 

Hey Velder:

That is a lot nicer than my 87 VDP parts car.
It has a decent interior it seems. Here is a bit of trivia, it actually has a Sovereign interior, which I feel is more cosseting than the firmer Vanden Plas interior.
Soveriegn is technically a six cylinder car. and in Canada a Sovereign is never a V-12 car. Yet a Vanden Plas is always a V-12 car here but could sometimes be had with the Soveriegn interior. Got that?
My '87 Vanden Plas has a VDP interior and my '89 Vanden Plas has a Soveriegn Interior so I have one of each.

Also another bit of trivia the exhaust tail pipes seem to be positioned exactly correctly. (Yes there is a spec for that) Meaning it may never have been replaced, or if so it was done at a Jag dealer. Value that at about the cost of a good Series III example that you could get right now, about $4000.
Based on these and a few other observations it seems to be a basically solid car.

Fix it up and you will lose your shirt on it.
In Canada Toronto is always the cheapest place you can buy these things and right now the best of the best examples are changing hands for $8000 at the most, and that should be a car that could go to pebble beach.
Sure there are a few nut bars asking $18000 and $12000 and even more but these people are delusional or perhaps are not serious about selling their cars.

The best of the best average cars with a bit of miles $4000 to $6000. Most of them have way less than average miles so don't be fooled by the odometer, low kliks is not actually that big a deal .
I have only seen a couple with more than 200.000 KM's on them and one of them is my '87 with 245000. An average mileage for any other 1990 car in average use would be well over 400.000 by now. So again they all have low kliks. A V-12 cared for in an acceptable manner will exceed 500.000 km's with ease.

Front fenders in good nick sell for about 3-400 CDN a piece. I have a right hand front wing hanging from the ceiling in my shop covered with dust that is in as new condition as in never been on a car almost.

It takes an afternoon to swap the fender (wing) yourself or fix the dents in place for the same or more time and money but then you still need to paint the car in either case.

Engine weighs about 700 pounds in the car stipped down to the bare block maybe half that or less..

And in conclusion, I have scrapped cars in that condition and better.
Come to Toronto and I can take you to a yard with 145 Jaguars in similar shape and more than half of them are series III cars. (I am feeling pains in my stomach now)
If you DID fix it up a Chev engine would NOT help your situation in any case as you still would have to do everything else as well.
So with all this I feel you will not be encouraged to fix it up as much as I would love to find out that you are as nuts as I am.

Wow this is a very painful moment that always hurts to realize.
Truth hurts none more than me.

JustV12.

 

Oh yeah and one more thing, that car has the desirable "pepper pot" wheels.
Those wheels alone are worth the hundred bucks you paid.

 

Do I need any thing over and above a decent screwdriver set and regular metric and standard socket set (plus a good set of wrenches) to yank the engine on this old girl? For example when changing stuff out on my 2002 Jetta TDI, you need like some fancy triple square sockets to do some of the work on it. Is it better to yank it with tranny attached or do you need to separate them? Does the engine come out like most rear wheel drive cars or do you have to drop it out of the bottom like a newer camaro? Thank ypou for your help.

 

It's easier to pull the engine and tranny as one unit. Pull the hood, upper radiator support, radiator, a/c cooler and oil cooler. Remove the air boxes and upper heat shield and you'll be able to get to engine mounts and exhaust. Drop the transmission mount (be careful, it's spring loaded) and disconnect all wires, lines, etc., then pull engine out and up. You'll need a good heavy duty crane because the engine alone weighs 700 lbs, with the tranny attached you've got another 150 lbs on it.

 

on a side note, is this a distributor engine? I know it is injected but could a guy make an intake, put a carb on it (or 6 or even twelve), and run it like that? On old small block chevys you could just feed a live wire to the distributor, cross the two terminals on the starter and she would turn over and come to life (if it had a carb). I work at a metal fabrication shop and we have 3D software so we could come up with something pretty nice. By the way, thank you for your help, it is very informative and I am enjoying learning about these cars.

 

Actually it would be very easy to make it into a carb engine. The intake manifolds don't have any coolant running through them and it's just 2 bolts to each port. And, yes, these engines have a distributor and I believe yours also has a crank trigger. I'm not an expert on the Marelli ignitions but I don't think it would be terribly difficult to change it around a bit.

 

Don't forget the V12 originally was a carburettor engine, Strombergs, I believe. The ignition should work without the fuel injection ECU being present, AFAIK they are not connected. Essentially you would be backward engineering the engine, but remember the HE engine is very high compressionn so will need careful setting up with carburettors.

If however, your present Marelli (or is it Lucas Opus ?), engine ignition system needs the ECU, just replace this with the old ignition system. It is a distributor engine, the distributor is driven off a jackshaft in the centre of the V.