The story really starts with the Austin A105 Vanden Plas, which was a specially trimmed and furnished version of the A105, personally inspired by Leonard Lord and produced in 1958 and 1959. It was such a publicity success, for absolutely minimal investment, that when the time came to launch a new large BMC car, the up-market Vanden Plas version was clearly desirable.

First, however, we must clear up the question of the marque badging. From 1946 to summer 1957, every car produced for Austin by Vanden Plas, at Kingsbury, was badged as an Austin. Then, without changing the cars in any way, the Austin Princess IV of the period was 'de-badged', and officially became known simply as the Princess. This was the situation in the autumn of 1959, when the new large Farina-styled saloons were born. Officially, the Vanden Plas version was to be known as a Princess 3-Litre, even though the general public still tended to call it an Austin Princess 3-Litre.

It was so confusing and unsatisfactory that BMC changed everything around again, so that from May 1960 the same cars became known as Vanden Plas Princess 3-Litre. All clear now?

Whatever the title, the Vanden Plas-produced 3-Litre was structurally and mechanically identical to the new Austin A99 and Wolseley 6/99 saloons. The cars took shape at Cowley, alongside the Wolseley 6/99 model, but were still incomplete when delivered to Kingsbury, in North London, for furnishing and completion to Vanden Plas standards.

Compared with the Wolseley 6/99, therefore, the Princess 3-Litre had a prominent special grille and an overhanging bonnet panel, and there were special wheel nave plates and paint schemes to add to the air of exclusivity.

The interior was entirely special, with a fine-grain walnut veneer instrument board, special instruments, specially trimmed and padded seating, and a great deal of extra sound-deadening to help make the passenger compartment as quiet as possible. Because of the type of clientele these cars attracted, a higher proportion of them were fitted with automatic transmission than was found in the Austin or Wolseley equivalents.

Even though the 3-Litre was obviously developed from a more 'mundane' machine, it still exuded a general air of added quality, was carefully assembled, and it sold well. The Mk II which followed was an even better car.

 NB: Princess 3 Litre was produced from 1959 to 1960

Vanden Plas Princess 3-Litre specification

Produced: Kingsbury, 1959-61. 4,719 cars built.

General layout: Pressed-steel unit-construction body-chassis structure, in 5-seater, 4-door saloon body style. Front-mounted engine driving rear wheels.

Engine and transmission: BMC C-Series, 6-cylinder, ohv, in-line. 2,912cc, 83.34 x 88.9mm, 103bhp at 4,750rpm; 157lb ft at 2,300rpm. 3-speed gearbox, all synchromesh, with Borg-Warner overdrive on top and 2nd gears; Optional Borg-Warner 3-speed automatic transmission; steering-column gear-change; live (beam) rear axle with hypoid-bevel final drive.

Chassis: Independent front suspension, coil springs, wishbones and anti-roll bar. Cam-and-peg steering. Rear suspension by half-elliptic leaf springs. Front disc and rear drum brakes. 7.00-14in tyres.

Dimensions: Wheelbase 9ft 0in: front track 4ft 6in; rear track 4ft 5.25in; length 15ft 8in; width 5ft 8.5in; height 4ft 11in. Unladen weight (approx) 3,465lb.

Typical performance: (Automatic-transmission version) Maximum speed 97mph; 0-60mph 17.9sec; standing 1/4-mile 21.4sec; overall fuel consumption 17mpg.

Launch Price: £1,397

Distinguishing features from previous models: Entirely new monocoque with unique styling, not connected with previous Vanden Plas-trimmed Austin A105 model.

Derivatives: Originally car was badged as a Princess, but became a Vanden Plas Princess from May 1960. Mk II model followed in late 1961, and Princess R derived from this in 1964. Car was itself derived from Austin A99/Wolseley 6/99 design of same period.

Fate: Discontinued in 1961 in favour of Mk II model.

Source: "The Cars of BMC" - Graham Robson (Motor Racing Publications, 1987)