New plan in place, off we go again. The quest to race at Cadwell Park sends me hunting for alternate places to race her when we’re done. The pre-93 Touring Cars look interesting. I won’t be at all competitive, not by a long, long, long way, but they’re going to Cadwell, and there will be BMWs to play with. I like snacking on Beemers, they are good sport. The properly quick ones do have an annoying habit of making me look very silly though.

A quick sneak at the regulations suggests a class F car, without my ballast, would fit straight into their series, and in fact Bear’s class E car with the glass refitted and a smidge of ballast would appear to slot straight in as well. Problem solved then, we have our Cadwell race. Hurrah. You have to race at Cadwell, you just have to. It’s inconceivable to not go, I’ve been in love with that track from the first lap back in ’07.

The concept of racing Helen with someone other than the JEC, at all, had never really dawned on me before. Thinking about it for even a few moments does make you look at the stripped shell, and wonder whether F class is the spec to rebuild her to. The decision is made there and then, she will be built to the alternate regulations, albeit able to go class F with about an hour’s work refitting the less trick bits. It is trite to say, but if you’re building a race car, which we pretend we are, there can be nothing more important in your mind than the regulations you’re racing under, and building her to do two jobs is a little more of a challenge.

Several pieces are now removed. Engine and box, wheels and tyres, seats and glass.

Now the car can be rotated onto her side, because I want to get to her underbelly and work on a few things under here with all the suspension in place.

The car is going to gain rebuilt subframes, the rear will be further strengthened, the front will get some help in the beef stakes too, and both want to be more positively located, but within the rules. In addition, they want to look pretty. We’re really going for it, this is going to be shiny.

Why leave it in place? Well, to make sure it fits. Nothing worse than modifying things and finding they won’t fit the car afterwards.

Positively locating the front subframe but retaining rubber mounts is a real challenge. We do, however, take our guidance from a member of the race committee who flogs those Harvey Bailey “anti-tramp” systems – so long as there is a rubber bush in there, however thin that rubber might be, then it’s not solid mounted and is therefore class F legal – and that does allow us some freedom to play.

The rear subframe will therefore gain our own version of that HBE system, only it will be a substantial redesign, as we don’t actually agree that the original works correctly. In order to further locate the subframe laterally there are arguments in the Kutuka garage about designs that feature a variant of either a Panhard rod or a Watts linkage. Arguments for and against each system are profound, and lead to brothers throwing hammers at each others’ feet.

There is, of course, an easier way, which is to make everything solid, but that’s E class territory. I want to solve the problem of class F handling, and it is a different challenge.

As she comes apart, a snag list of jobs I want to do, and pieces I want to change and modify appears on the stolen whiteboard. There is a lot of fabricating and a lot of big holes to bore on that list. Everything gets swaged. Just because I can. Our car prep has moved on again in the three years since I first did this car, and she can be made better.

The chassis will be made stiffer. It’s already seam welded and braced, but we can do better yet. A few extra gussets welded in won’t cost much weight and will add a few percentage points. Key to this, I think is the front end of the car. The lower chassis is very deep, but the top chassis rails, those box sections, aren’t joined to the lower by very much really. I’ve always largely disregarded anything forward of the shocks, but really you can’t ignore the fact that the subframe is mounting a long ways forward of that, and a bit more strength in this area would be helpful. Knowing how good the front end on Vanessa was and what we did to that car it is unthinkable that we should not duplicate that for Helen.

That includes bracing the radiator crossmember to other areas at the front, which when combined with the bumper mounting bars we fit these days – Helen being the first of our cars to gain these after Cadwell 2009 – has the effect of substantially stiffening the front of the car to reinforce the 4-box structure.

Taking that to its logical conclusion, the front of the car - firewall to slam panel - is a box with the four box sections linked by firewall and front panel. Helped beneath by the radiator crossmember, and above by the diagonal braces that reach from firewall to front strut, there is nevertheless a yawning chasm left unsupported, and this rebuild needs to try and address that. I wonder how much rigidity is lost by the cars that cut so much metal away at the front? Jaguar obviously thought the car needed help here, hence those cross brace bars they sport.

An additional crossbar made of CDS is joined to the oil cooler panel, and from there more bracing spreads to integrate with the other structures. It’s about 3kg of steel going in, which is quite a bit, but I’m prepared to take the balance penalty in the interests of stiffness.

The headlight pods lose a little metal from the inner skin, already done on the nearside for the air intake, a standard F class mod, but now duplicated on the offside to allow more air in. More for symmetry than need really. I’m not sure I buy the need to cool the electronics, but if you can, why not?

The oil cooler always stood a hint too tall, a big cooler with big adaptors, it hit the bonnet and caused a little “power” ding, so I need to lower that slightly. To do so, however, means cutting a lump out of the panel to recess it down into the car by that half inch it needs. It’s either modify the panel, or go back to Pirtek to get new hoses, and at about £120 I think the angle grinder gets my vote.

Technically that means I’ve cut some steel out of the car, so that’s a lightened panel. Sadly no weight is saved, because to brace that panel back to full strength and come up with some recessed mounts to hang the cooler that crucial bit lower means putting more steel back than comes out, the panel is not so much lightened, as redistributed. Semantics perhaps, but the rule is there to stop people chopping metalwork out and running about in a lightened car, and we’ve certainly not done that! These little changes take a lot of time, but if you want to run custom parts.... Which is why race cars are expensive.

The restored panel is strong enough that I can walk on it during my many trips in and out of the engine bay. You can’t do that with the original.

A few extra gussets appear, linking chassis to inner wing. Any tiny extra degree of strength I can find gets my attention, spread the loads that little bit further. To a large degree I’m wasting my time, the inner wings are so floppy on the XJS that you could argue that bracing anything at all to them is about as much sense as building castles on sand.

The amount of thought, and time, and trial and error that goes into this sort of thing is totally disproportionate to the net result. But, it’s my car, so if I want to I will. I know I bang on about Cadwell, but the confidence to turn into that first corner flat in 4^th without braking, that comes from knowing I did stuff like this. Even if it didn’t help the car one bit, it helps my little brain, because I believe…

The stripdown at this stage leaves her a rolling shell only, not one component left attached but the subframes and fuel lines. I predicted 3 days to strip her. It took exactly 3 days. The welding and fiddling will take a week. She must be in paint by the end of January.

The long job of sanding the exterior has already begun, because the attention to detail missing last time is to be corrected. The door apertures, screen surround, rear window, boot opening etc, most of them were quickly sanded and painted, without a deal of care, and I think you can tell, she has always been a red car painted blue, so a great deal of time is spent sanding the offending areas of paint back to metal. There is so much car, and it has to be done by hand, so it is a classic case of half an hour on it, then revert to real work for light relief.

She now awaits my attentions to her underside. My obsession with airflow will also require some time playing under here. I read a book on it, OK, and I’ve had the bug for aero ever since I had to teach principles of flight. If I stand on my head they all still apply....

HELEN: Resurrection

JAGUAR XJS RACING

I may have spent Christmas doing a little fabrication work, starting with a new radiator panel.

In full stripdown mode now, but the bits jump out awfully quickly. It's like we planned it.

This car only got a partial rewire first time round. This time will be very different.

The boot always amuses me. Air horns, the road horn and washer bottle for class F legality, and heater valve the regs say must be fitted - but not where! - all live back here.

Happy new year?

The problem with stripping them down is how much space they take up when in pieces.

As a roadgoing class car with no weight issues, we filled her with daft touches that you only remember as she comes apart - like the furflex trim!

It's amazing how much crap collects in the various nooks and crannies, this pile of silt and shreds of rubber shouldn't really have even managed to get in here.

The gearchange has been extremely sloppy for years, only driving other cars this year really brought that home. And here is the reason under repair.

And with it fixed, the short-throw gearchange I fitted two years back suddenly makes a lot more sense.

I will have to re-learn the gears!

Oil cooler panel being modified.

Chopped out, and then welded right back up with five feet of cds tube.

Lightened? Hardly.

Ballast. And the seatbelts. Both of these a consequence of the monumental 2010 weight limit.

Yes, we really did pour molten lead into the back seat.

More ballast. This time from the original build.

Yes, there's more of this elsewhere too.

The rust stains aren't a problem, but still, they spoil the shine.

And we're still finding shot.

Last of the interior being removed.

The silver alloy tube was the vacuum feed. For the original, standard Jaguar ecu.

This car came fitted with an AJ6 engineering ecu. Which we took out.

To be honest, I quite like the look without the bodykit, suits the colour.

Taking this shot from the rafters was bloody dangerous.

Time to lose the fuel filler flap. It was sealed shut three years ago as we have the fancy alloy filler, but now it is to disappear completely.

First welded to the car, carefully to avoid heat distortion, then ground back, scurfed, filled and sanded.

Two hours for one tiny, tiny change. Our cars would cost a mint if we had to pay people.