Jaguar XJS V12 racing car

[AdeV]

So... not a lot new under the sun, but I did get photos of the newly welded in panels. Damn, but welding to rust hurts (sparks, t-shirt, pain)... I clearly need plenty more practice with the MIG too...

The photos show a panel which rises vertically from the rear of the floorpan, up to form the front of the rear seat base. The rear seat bottom then runs downwards at 45 degrees (roughly), intercepting another panel which runs horizontally backwards from a couple of inches above the floorpan, which then curves up to allow the rear subframe to sit in place. It's a bizzare affair, but it does make a nice strong triangular section. Nice and strong, that is, until the water gets in & can't get out, at which point it starts eating....

Anyway, I cut the floor pan back, made a cardboard template of the area in question, cut the sheet out & welded it in. The first one got some plug welds in the middle for extra pizazz. The second one didn't because, well, I forgot OK. Too keen to play with the power tools....

[micktoon]

Ade , you deserve a medal for doing this job mate ...............its making me crindge looking at the rust , it always ends up more than you first think and leads to more ....and more .....and more patches  , one thing for sure you will be a good welder by the time the job is done .
 I wish you all the luck and may you find good steel often 

  Cheers Mick

[dawesy]

Looking good. A tip I use for car body is use a lowish current and pulse the trigger. Also although you normally 'push' mig I then to point the wire away from the direction of travel so the wire goes into the pool. Stops it burning away so easy.
Like I  say though nice job

[AdeV]

Thanks again lads - all encouragement is always appreciated....

This weekend was "tackle the rusty chassis rail" weekend.... so, the panel was prepped:



There used to be a flange there where 3 panels all met & were welded together; but the flange had rusted to almost nothing. So, I've decided to simply weld a flat plate over the lot, it'll be seam and plug welded in, so should be plenty strong enough:





Welded in:


Grind back the welds, and blow over with some weld-through primer:


The other side wasn't quite so bad, just a bit frilly around the edges. So a smaller patch was made & welded in:


Then tittivated:


Finally, the outer box strip is formed, and welded into place, before being tarted up with a quick spray of the silvery stuff:

[Divided he ad]

Ade.  You're a bloody mentalist!     


You should write a book... Masochism for engineers! 



Looks like you're well into the job now, I may have to pop over for a visit?   



Ralph.

[AdeV]

Ade.  You're a bloody mentalist!     


You should write a book... Masochism for engineers! 



Looks like you're well into the job now, I may have to pop over for a visit?   

Everyone seems to think I'm crazy for wanting to rebuild this rusty old hulk.... 

Still, who am I to argue? I know I'm crazy 



Ralph- you definitely need to pop around for a tea coffee hot beverage cold one, any time. I've got a fridge full of Budweiser & San Miguel. And a pool table.... Oh, and most of a Jag XJS 

Floors are going to be a challenge...





If there's a God of Rust - then what remains of this car is a temple to him, and continues to make generous offerings....



The two rectangular things were an absolute corker of an idea from British Leyland (or whoever the hell invented them)... they sat in the floor pan, inside the "sticking down" bit of the swaged shape. Thus trapping any water which got into the cabin, and giving it maximum time to rot its way out. It worked a charm.... Weirdly, on the inner sills, they got it right and used a thick layer of underseal, to which was bonded a foam layer (which had NO contact with the metal work, thus keeping any moisture at bay), the carpet was then stuck atop all that. It worked a treat - the inner sills are in perfect condition, right the way to the point where the underseal layer stops.... if only they'd slathered the whole interior with that stuff - yes, it'd be a nightmare for me (I am removing it for weight reasons), but it would have saved me 6 months of cutting & welding practice!

[awemawson]

Dunk the whole thing in a vat of citric acid. Go away on a couple of weeks holiday, and when you come back what is still steel will be revealed - probably looking like a fallen leaf that has already gone through autumn and winter, and it now rejoicing in the warmth of spring 

[micktoon]

Hi Ade ........are you sure that's not Fred Flintstones old car  ............. I am sure him and Barney had smaller holes in their floor !
   Its amazing to think every car in the scrapyard was in that state , now they all just look like they are parked at the shops, no rust just sensors etc have wrote the car off for scrap.funny old world 

  Cheers Mick
 

[Divided he ad]

I'll drop you a text Ade.

Bit busy at the mo.... But I'll get in touch Soon. Honest 


Still can't believe your welding up an XJS!   




Ralph.

[DavidA]

All this goes to show that virtually any car can be brought back to life.
But , and I think Ade will agree with me on this,  the most important thing is to really look at what you are going to replace before you cut it out. And ask yourself 'is there something I can fix my new part to ?' Just chopping out great swaves of rusty metal will leave you with no reference points,  or anchorage places for the good metal. You have to plan well ahead.

It may be hard, dirty work (and it is) but it is very rewarding.

Dave.

[AdeV]

But , and I think Ade will agree with me on this,  the most important thing is to really look at what you are going to replace before you cut it out. And ask yourself 'is there something I can fix my new part to ?' Just chopping out great swaves of rusty metal will leave you with no reference points,  or anchorage places for the good metal. You have to plan well ahead.

Yep, I definitely agree with that... I'm very nervous of moving stuff around on the chassis; even though I don't plan to use most of the original anchor points (unless absolutely forced to).

Also, you'll notice that all the bits I've replaced so far (including the 2 floor panels that I've not photographed yet) are pretty easy shapes to produce. There's some interesting recurved pieces to come which I've no idea how I'll make.... I'll probably outsource them to the chap next door, who loves doing this sort of stuff.

I also want to widen the back of the car by about 2" each side, to fit wider wheels, but I need to (somehow!) keep that iconic XJS profile. I'm thinking of ordering a few kgs of plasticine and doing the classic car design thing - lump it on there, shape it up; and once I've got it spot on, I'll make a fibreglass mould, and use that to make a carbon fibre panel. Then, either cut out the original metalwork; or just leave it in (weight over the rear wheels isn't necessarily a bad thing on a rear-drive car), and bond the CF panel to the original metalwork. Ambitious, I know.... but I like the idea much more than I like the idea of trying to form it in steel...

[nel2lar]

It is a great thing when something that will never be made again is brought back to life. A Jaguar XJS V12 race car is a special mo-chine. I live in the USA and the cars sold here are not the performance models, they are the cut back standard with all the emissions that rob horse power and performance. Many years ago a man I knew bought a Porsche 911 Targa Carrera while in Germany. He brought it back to the USA and came to the relization it was a race car and not legal in import. The last time I heard it was still in his garage under cover. When driving you could shift 1st, 2nd and 3rd gear and never be able to sit forward.
It had so much torque at 55 mph you could pull it back into 2nd gear and take off like a rocket. Too bad the Jag has an automatic but much nicer when touring. Looking good, keep us up to date I would like to see how it comes out.

On another build, check out this site, it has some 36 pages but it is more than worth it. The site is:
http://forums.aaca.org/f190/construction-continental-mark-ii-model-scale-278354.html

Cheers
Nelson Collar   

[AdeV]

Thanks Nelson, I do intend to stick a proper manual gearbox in - either an American Tremec (which is a bolt-in replacement for the autobox, apparently); or I might put the Toyota Supra R154 box I already have in (but that will need engineering work at both ends to fit properly); final option would be a 6-speed BMW box, but that's earmarked for the Granada project now... So, we shall see. I'd prefer to get a 'box with straight cut gears, for that authentic race-car whine (and better strength, of course).

Meanwhile.... more of the same old, same old. Find rust, tidy up around rust, make plate, weld plate in, blow over with zinc primer, rinse & repeat....

Pics show: The plates I made up to close the holes I cut in the floor. A new plate on the inside of the cabin which go where the front of the back seats are. I'm not sure what that bit's called. Anyway, it's frilly as hell, so it gets beefed up. Finally, the rear seat back corners are holed on both sides, so a plate is made up to cover the damage. Lacking the properly shaped hammers, my colleague used the back of an impact screwdriver to make the basic curve shape, tack welds were used to keep everything in place while the next bit of corner was made. Just visible in the last picture, is a V-shaped piece which ties the wheel well back to the body of the car...

I haven't started on the floor pans yet....

[DavidA]

Just decided I need more cornflake boxes.

Dave.

[AdeV]

Since the last update, a couple of months ago, a lot of thinking, planning and general other things which don't involve any actual progress have been going on....

First up, to stay in my chosen class, I am sorely restricted on what I can do. So, widening the car is a no-no, as is fattening and lowering the sills to contain the exhausts. I can't say I'm totally surprised at this, but it's a tad disappointing nonetheless. So.... I have to work out what size wheel I can fit under the arches as they are, and work accordingly, I can still tweak the offsets to fit slightly larger width wheels in the back, not sure what I can do with the front. Time will tell...

So... I've been thinking about engine stuff. Having decided a complete strip down will be essential (if nothing else, the chain tensioner is likely to want replacing), then I might as well go bananas on the engine instead of the body work. That way, if this one bites the dust, I can use the engine in something else...  As it happens, the racing car show is on in just over a week, so I'll be going to that, and I will be tackling people about ceramic coatings, fancy pistons, custom ground cams, etc... I figure a budget of around £5k for the engine should see me getting between 600-700bhp, depending on how well I can make it breathe.

And, conveniently, that brings us on to some actual photo progress Having made the lower part of the inlet port adapter plate some time ago, I finally got around to making the upper part of the plate - still in wax, this is just a prototype. As usual, I drew it first in SolidWorks, then imported to CamBam, a spot of fettling in CamBam, make the "G-code" (Heidenhain code actually); throw a wax plate I'd made earlier onto the machine, line it up, and go! Almost unbelievably (not quite... I'd used paper test prints) the throttle bodies fitted right on, and sat nicely over the existing plate. The green one is the new plate, the cream coloured one the old "underplate". The two will bolt together to form a complete piece. I have to make it in 2 parts because there's all kinds of interference going on - the head bolts get in the way; the heads themselves are in the way, the mounting bolts on the under plate are mirrored in the middle of the engine, it's chaos down there. Meanwhile, the BMW throttle bodies all sit in a nice line with all the bolts in the same direction, which just causes problems:











Overall height was a concern - but it turns out that the top of the highest point of the inlet is still (just) below the top of the filler cap; so I should have some room under the bonnet. If it's a bit marginal, I'll cut holes in the bonnet to let air in that way. Also, I can shave about 8mm off the combined height of the two plates, and still just about have enough metal to do everything I want to do with it, so that'll be done for the final versions.

I've still got the flywheel to design/make... that will be interesting...

[Stilldrillin]

Nice to see more of your waxworks, Ade! 

Wax flywheel, perhaps?   

David D

[AdeV]

The time has come to bite the damn bullet and strip the engine down to its component parts for thorough cleaning, measuring, etc.

First off, "B" bank cam, cam carrier, and head is removed. This operation goes surprisingly easily - I was expecting a bigger fight from the head, in the end it virtually popped off all by itself. The interior of the engine is dirty, and has collected a fair amount of debris, kind of what I expected really.  Everything seems to be in relatively good order though, although I have yet to measure everything & check for warpage, etc. A good soak in solvent plus some vigorous scrubbing is bringing the parts up like new (no photos of the clean stuff yet).

[AdeV]

Stripping "A" bank revealed a bit of a problem... No 2A has had a small washer - about 1/2" diameter - banging around in the combustion chamber for an unknown period of time. The piston has taken the brunt of the beating, but there's some damage to the head as well. Hopefully, it's all repairable with a TIG welder, some filler rods, and someone with a decent surface grinder.

[AdeV]

So... strip-down wise, there's not a lot left. All the studs came out - eventually, and in one piece - unlike my Halfrauds stud extractor set which balked at the 2nd head stud! Thank goodness for the rather more robust Draper unit, although that has its frustrations; it has a tendancy to come apart into its constituent components as you try to free the now jammed in stud. Hey ho.

So... sump to come off, oil pump, rods & pistons out, main caps off, crank out, liners out, and then we can begin cleaning & measuring the block...

What is coming out: 5.3 litre spec liners, pistons, rods, crankshaft.
What's going in: 6mm bigger liners (96 vs 90mm), same rods, new shorter pistons, 6 litre crankshaft.

The crankshaft will give me an extra 8.5mm stroke, the bore an extra 6mm diameter, all told I should end up with an engine that displaces 6.8 litres (416in³) and - if I can get the volumetric efficiency up where I need it, I should see north of 600bhp and 480lbs/ft torque...

There's not a lot of machining involved in the next bit of the engine build, but there is quite a lot of expenditure (the pistons are the big ticket item, and I expect them to cost around £2000 (US$3000)), which is going to slow me down a bit...

[vtsteam]

Ouch, and it would be a hardened spring washer, too. Looks in perfect shape!  You're doing a great job here. Nice to see this car coming back to former glory. Well surpassing it at some point. 

[dawesy]

Ouch. Hope it's all repairable.
On the cleaning front I use Swarfega oil and grease remover (£9 for 5ltrs at B&Q)
Works wonders on baked on grime and doesn't really smell of anything unlike the solvent based products

[edward]

I am probably being totally ignorant of something obvious here, but how in hell does a spring washer end up inside a piston - has it been there since build?

[RussellT]

Well if there are washers under the heads of air filter housing mountings they can be sucked in.

It happened on one of my cars (a long time ago) on the A1(M).  It made a dreadful noise.  I got it towed off the motorway and took the head off on a garage forecourt to extract the washer.

I'm following with interest Ade.   

Russell

[edward]

interesting. I'm amazed there is space for it to fit, but then I guess for good gas flow the spaces should be big!

Something about the A1(M). Years ago the timing belt on my old faithful 1992 Astra estate went ping while I was in the outside lane there - a real brown trouser moment as it was busy and I had limited momentum!!

Ade - you are mad, but in a good way:)

[AdeV]

The pre-HE V12 actually has quite a large space (0.150" at TDC) between the top of the piston and the head, so there's room for the washer to sit in there & fly around the place. All the dings are half-moon shaped, so it's obviously when it's landed edge-on that it's done the damage.

Given that the heads were relatively easy to remove, I'm thinking they've been off before - probably not that long ago in mileage terms. I'm also thinking they re-used the head bolts, judging by how well held in they were by comparison... I imagine the washer got in the last time any serious work was done on it. If you leave the inlet manifold on on a normal Jag, it's almost impossible to get anything into the cylinders; if you take the manifold off, it's almost impossible to keep stuff out!

Apparently, Jag V12s are prone to dropping valve seats if they're overheated (being an interference fit), but because there's so many cylinders and so much sound deadening in the cabin, all that can be heard is a faint tinkling sound - even though the seat is being beaten to a pulp by the valve...