Feasibility study: LS-swapped XJS

Hey guys, been a GRM reader since the mid-90's, when I was a cash-strapped teenager with an AW11 MR2 and big dreams. Now I'm a cash-strapped adult with an Impreza wagon and the bizarre yearning to try my hand at a conventional-yet-not swap. LS engines have probably been swapped into Hillman Imps, so I don't think I'm being too out-there with this idea. Fab work is a given, and I don't mind learning as I go. Engine will likely be a 5.3 Vortech because iron is cheap and durable; transmission-wise I'm looking at a T5 or a T56 if I somehow win the car parts lottery. Curious if anyone has tried this (searched the boards in a cursory fashion, but I like interactive feedback) or if some XJS owner out there has tips, advice, taunts, bad names to call me, etc.

Edit: Also, if I need to shuffle this off to a different sub-forum, lemme know.

http://www.jaguarspecialties.com/XJ6C-P1.asp

Ah yes, I remember seeing that when I first started dreaming this project up a few years ago. Prices aren't terrible, but my masochistic side says "do it yourself." I can't drink that part of me away. Anyway, now I wonder if anyone here has used one of those kits...

I have no personal Jag experience (yet) but I have lusted after one for years. From what I have gathered, the V12 is not really the problem with those cars. In fact, the V12 is actually a really good engine, limited by poor supporting components. If I had an an XJS or XJ-12 sedan with a healthy engine, I wouldn't dream of swapping it out. I would probably try to megasquirt it along with a DIS ignition system of some sort. The V12 is the best reason to have an XJS. Manual gearbox XJSs are quite rare, but the AT units are GM th400 or 4l80e. Cheap, tough, tunable and rebuildable.

If you find one that does have a bad engine, the buy in should be really cheap, and I wouldn't criticize an engine swap. Keep in mind the rest of the car will still have dodgy British Electrics to frustrate you.

Your new best buddy

There was a guy on here who used to advocate for jags as cheap track cars, said once you remove a lot of the creature comfort stuff they are actually pretty reliable

As a person who has to work on Jags I have to ask. Do you like shims? Do you like shimming things, Assembling units 3 or 4 times to get the proper amount of shims in place. Ordering expensive, non-returnable sets of shims because you have no idea which ones you might need beforehand.

Look at the amount of spacers and shims and spacers inside of shims in just this diagram. 10 through 15 (actually seven shims!) are just one side of one arm pivot and will be repeated on the other half of the arm, You can see three more that aren't even labeled. I can guarantee you there are at least 5 more you don't know about. Now I want you to understand that every suspension pivot on the car has a similar layout.

I find these cars infuriating in a way that no other car has ever been. Our main mechanic tech Paul has the ironic job title of "head shimmist" aka "Master of shimmistry" or just shim-ologist. These things just have so many unnecessary complicated pieces when just one properly designed piece would do. Of course 56 shims and spacers per corner is "proper old world craftsmanship" and that new fangled well designed stuff is lesser for it somehow. Jag enthusiasts are a strange and vocal breed.

Jumper K. Balls wrote: As a person who has to work on Jags I have to ask. Do you like shims?

Well, I... I hadn't thought about my stance on shims until now. The stark moment of realization that I may, in fact, have an overconfidence problem, came when I read this (and the other excellent responses, thanks guys!) and still found myself asking "well, how hard can it be?"

Truth is, there is a bent appeal in working on something with, uh, personality, and since SWMBO will cut my hands off if I buy an Alfa, a quirky Jag seems like the next best thing.

I'm not clear what your spouse's problem is with Alfas. Frankly, a demanding Italian mistress who keeps you close to home seems like a better alternative than, well, a couple of others I can think of.

paddylopez wrote: Ah yes, I remember seeing that when I first started dreaming this project up a few years ago. Prices aren't terrible, but my masochistic side says "do it yourself." I can't drink that part of me away. Anyway, now I wonder if anyone here has used one of those kits...

When it comes down to the "Buy or Build" decision, I look at the amount of engineering involved. I am pretty good at figuring things out, and the fabrication tends to come out pretty good. On the second or third iteration.

Sometimes I am good with that since I enjoy making E36 M3 for the fun it of. Other times I look at the part available for sale and realize that the $$$ will be a wash and the big saving will be in time and a somewhat proven? component.

Here is an example: You made engine mounts. You made headers. You realize that somehow the two interfere by 1/2". You can see 1/4" gain in the header and the mount, but not 1/2" in either one. So, do you remake the header and the mount or say "Good enough for the girls I go with and whang a 1/2" dint in the header pipe? Engine swaps are full of these kind of setbacks and can be heartbreaking if you are not the type that likes to problem solve. The kits on the other hand, have already run into and solved all the set-backs.

In reply to Jumper K. Balls:

So what you're saying is, if something suspension wise in my Jag (03xtype) I should just sell it? Or rather just replace a whole unit? Or is this mainly old Jags?

But regards to OP, Ive no first hand experience, but your best bet would be to check out lsJuan tech, that is if you are brave enough to ask the question without being bothered be the shiny happy people that will say USE THE SEARCH BAR!!! Amongst other things. I havnet seen much bickering over there lately, so it may have gotten better. But either way, if you were to google it, chances are it would take you to them anyways. Just my opinion.

In reply to BeardedJag:

Your X-Type is one of these cars; http://en.wikipedia.org/wiki/Ford_CDW27_platform

I doubt there's a shim in the entire car for any purpose.

In reply to pres589:

Yea, I knew it is pretty much a ford taurus, but i didnt know if they had changed anything about it to make it more...Jaggy. But after actually seeing that, kinda makes me want to sell it now haha.

In reply to BeardedJag:

It's not a Taurus, it's a Mondeo/Contour.

Meh, guess I didnt read it all the way through.

So, it seems that there's a healthy market for getting a manual transmission hooked up to the Jag V12, which makes keeping that motor a bit more appealing. If I do that, I understand that because of the way the exhaust pulses, the exhaust system is pretty decent in its stock configuration (high-flow cats, just because). One consistent take is that the intakes are pretty restrictive. If I stay with the V12 (which really sounds increasingly appealing) I would want to eliminate as much of the Lucas points-of-failure as I could, but I can look into that in the future.

As for the chassis, the inboard brakes on the rear subframe seem...less than optimal, and all this shim business is frankly a little terrifying, but if I wanted easy, I'd build on something else.

Ah my failure! I saw the X and thought XJ6 since they come up on this board so very much. X-types I know zero about.... thankfully

In reply to Jumper K. Balls: My neighbor had an X Type. He considered it a Lincoln and said there were many shared parts. I never worked on one myself.

Jumper K. Balls wrote: As a person who has to work on Jags I have to ask. Do you like shims? Do you like shimming things, Assembling units 3 or 4 times to get the proper amount of shims in place. Ordering expensive, non-returnable sets of shims because you have no idea which ones you might need beforehand. Look at the amount of spacers and shims

I just made some throw-up in my mouth

In reply to Rupert: I don't want to flog a dead feline here, but your neighbour was confused. A Jaguar S-type and a Lincoln LS were close cousins under the skin, for whatever that's worth at this point. To my knowledge, the shared parts between an X-type and any Lincoln are pretty much Zip.