My Daimler Double-Six Vanden Plas Series 1

November 17, 2025

I like cars that were special or ahead of their time in their day. That could be in technology, styling, performance or they way they were built. One of the cars that fits this category for me is the Series 1 XJ with the V12 engine.

Both the car and the engine are masterpieces. The V12 Series 1 XJ was the culmination of Jaguar at their best and when it was launched in 1971 it was a revelation and the ultimate sports sedan.

The V12 engine was probably the most advanced mass produced engine of its period – An all alloy overhead cam v12 that started out life as a race engine and then was developed for the road. It was originally supposed to have fuel injection from the start, but the supplier cancelled the project and Jaguar came up with the quad carburetor setup as an interim measure. The engine is well built and strong, but suffers from prodigious thirst. The timing couldn’t have been worse for Jaguar, launching such an advanced engine right before a fuel crisis.

Even with the XK engine, the Series 1 XJ is a world beating car. The V12 just took it to the next level. I’ve always wanted to own both a series 1 XJ and a Jaguar V12, so it made sense to buy a car with both.

While a short wheelbase XJ12 was appealing, the model I really wanted was the Daimler Double-Six Vanden Plas. This wasn’t going to be an easy car to find. There were only 351 ever made, and none sold new in Australia. Survival rates are not great. In the 90s they were just seen as a thirsty old car, and pretty much worthless. Since most of them were sold new in the United Kingdom, rust claimed many. Private imports in Australia do exist, but there are few in good condition.

The Daimler Double-Six was an XJ12 with nicer trim, a different grille and more chrome. The Vanden Plas model took it to the next level. It started out with a long wheelbase chassis with all the available options except for the chrome wheels. This included air conditioning, fog lights, electric windows, remotely operated rear view mirror, Radiomobile 8 track, and Sundym glass.

The cars were assembled at Browns lane to a base coat of paint and then sent to the Vanden Plas Kingsbury works to be finished by coachbuilders. This included a sumptuous interior, special metallic paint colours and a vinyl roof. A regular Double-Six was £3,848.90. The Vanden Plas would set you back £5,439.06 as of October 1972.

I have been on the lookout for one for many years. One popped up for sale about four years ago, but I wasn’t in a position to buy at the time. It also didn’t seem like the car for me. After a while, I saw an interesting XJ12 SWB for sale in British Racing Green. Given I figured I may never find a Vanden Plas, I went to look at the car. I liked it, but it wasn’t the car for me.

A while after that drive I mentioned this to and old friend, who told me that a Vanden Plas he used to own might be for sale. It had been repainted and had a new vInyl roof fitted, but the current owner had two Bentley projects to do, and was thinking about selling the Vanden Plas. On the upside, it was rust free and freshly painted, and had a pretty nice interior. On the downside, it hadn’t been registered since 2005.

A deal was done after I went to see the car. It wasn’t perfect, but it was a rust free Vanden Plas. The interior wasn’t perfect, but it had a nice patina and was pretty original. Before I took possession of the car, it required some work to transport it safely.

Installing electronic ignition to get it to run properly
Ensuring it would not catch fire by making sure the carbies, fuel hoses and so on were all attended to
Making sure my lovely V12 engine would not cook by getting the cooling system to work
Fitting tyres that held air on the correct wheels
Making sure the brakes worked
Fitting some of the missing chrome from the repaint

With that work done, I was ready to take possession of the car. It still needs a few things to get it to the point where I would be confident driving it to Melbourne and back, but it runs very nicely when warmed up, and the engine stays cool. I’m very happy with it and am looking forward to slowly improving it over time.

So far the main thing I have done is take it on smaller drives. It runs better and better the more I drive it.