Now for something different. I thought it might be nice to every once in a while share a bit of automotive history, we had at Classic Restorations Holland. First up: the magnificent Jaguar XKSS.
The Jaguar D-type was a purpose built, Le Mans winning race car. But when Jaguar retired from racing at the end of 1956 there were still 25 of the 68 D-type racers left unsold. Jaguar decided to convert them to road going sportscars. To do so, they added an extra seat and door, a full size windshield, a rudimentary roof and a set of bumpers. This is how the XKSS was born.
However, on the evening of February 12th, 1957, a fire broke out at the Browns Lane factory. This destroyed the assembly line, some of the machinery, the plans for the car and 9 out of the 25 XKSS's. This meant that the 16 cars left, were the only XKSS's Jaguar would produce. Two of the cars were sold to buyers in Canada, one went to Hong Kong, one stayed in the UK and the rest went to America. This is the car that stayed in the UK. Today, this car is part of the Louwman Collection of the Dutch National Motor Museum at the Hague, Netherlands.
I asked a good friend of mine to review the exterior design of the XKSS. He is currently studying automotive design at IED Torino. At the bottom of this post you will find a link to his blogspot page, or you can click his name below his review.
'Because the XKSS is the road version of the famous D-type, the car's exterior is almost identical. They just added an extra passenger seat and door, a wind screen with side windows, a simple folding soft-top and a functional interior. Sadly they also had to remove that iconic fin at the back...
The designer of the exterior body is Malcolm Sayer, he was a former aircraft designer which reflects in the whole design of this car. He wanted to create a car with absolutely minimal frontal area to reach higher top speeds on the straights at Le-Mans. Also, the car's whole body is made as low as possible, again to create a small front and overall profile. The result was that the wheel arches then "sticked" up, out of the body. The same happened with the straight six engine, which created the beautiful power bulge. With a really soft aerodynamic treatment of the "fusion" between the car's body and the wheel arches it creates a unified sculpture.
It is this approach makes the car look so pure, every bulge is made for a reason and it shows the mechanical parts underneath its skin. Also, the proportions of the car are quite unusual as the car has an extremely low profile and both back and front overhang is kept minimal. This mix of ingredients is what helps making the car so unique in my opinion.'
In fact: even the agressive stance (or forward rake), is a result of the car's aerodynamics. Another feature standing out in the exterior is the rivets. As mentioned earlier, the XKSS is actually a modified D-type. The D-type was one of the first sports cars to feature a monocoque chassis. The monocoque was assembled using rivets, rather than welding, because in the mid fifties welding quality was very poor. Even modern cars with aluminum structural parts are very often still glued and riveted, because welding hardens the material locally, making it more brittle and weakening the structure. On the D-type they just left the rivets visible on the body, because it was never meant to be a show car. Since the XKSS was made to be as close to the D-type as possible, Jaguar didn't bother to rebuild the 25 remaining chassis using flush rivets.
The Jaguar D-type was the second car to use the revolutionairy Dunlop brake discs. As you can see in the photo above, these are a long way from modern racing brake systems. But remember, in the mid fifties brake drums were the standard. Pegaso for instance, built a car to defeat the D-type (I may feature that one when we've finished restoring it ;) ), but failed because the Jag could easily out-brake it.
The picture above also shows how the power transmission between the wheels and the axle takes place. As you can see there is no splined axle. Instead, this axle shows a flange with ten holes. These correspond to pins inside the rim. Anyone who has ever changed a tire on a classic car knows that the hub needs to be aligned with the axle splines quite precise. By eliminating the spline the chance that the wheel gets stuck is reduced. Now you can just stick the wheel on the axle, rotate it a little bit before the holes line up and the wheel is fully on. This pin and hole power transmission is how it's still done in F1. Also, to reduce the unsprung mass, the wheels were magnesium Dunlop's.
The engine in the XKSS is basically a 3.4 litre XK-engine. However, in the XKSS it was fitted with a dry sump oil system, allowing the engineers to mount the engine lower in the chassis. Also, dry sump oiling systems provide a more reliable lubrication, even under higer lateral forces during to cornering.
Anyone who looks at the photos above, and knows the XK-engine, will suddenly realize how small the car is. The engine hardly fits inside the packed engine bay. The XKSS engine featured 3 rare Weber 45DCO3 double carburators, and a double side exhaust system. Power output was about 250 hp at 6000 rpm, which was very impressive at the time.
If you are still not impressed with this little high-tech racer, I've got an illustrating example. Just consider a modern day equivalent for this car. Take last years Le Mans winner, the Audi R15. Add a passenger seat and door, a full size windshield and a linnen roof, then remove the rear spoiler. That's exactly what Jaguar did in 1957. It was mighty expensive, truly terrifying and extremely beautiful. This particular car is on display at the Dutch National Motor Museum. If you have the opportunity, you should pay it a visit. I know this car is also being driven from time to time, so if you're near the Hague on a sunny day, keep your eyes and ears open. ;)
The blogspot page of Bernd WeelWebsite of the Dutch National Motor Museum
