The TA 21 was Alvis' last completely new car design to reach production. It sought to move the marque back into a more expensive area of the market than the TA 14. Only the gearbox was carried on from the 12/70 through the TA 14, but many standard Alvis design characteristics could be identified. Independent front suspension, by coil springs and wishbones, was of Alvis design, mounted on a massive cross member. The 9'3½" wheelbase chassis had a frame of box section, the box being closed with a plate welded across the bottom. It was of still lighter section than the earlier chassis, yet more rigid. Rear suspension was conventional, with half-elliptic springs mounting a Salisbury hypoid axle. Telescopic dampers were fitted front and rear.

1950 TA 21 Mulliner saloon

Hydraulic brakes were featured at last, Girling units with twin leading shoes at the front, but the hand brake was a vile pistol grip affair under the dashboard. Steering was via a Burman Douglas unit. Left and right hand drive versions were produced. Wheels were 15" bolt on steel disc items. The engine was a six cylinder of 84 x 90 mm, 2993 cc, dimensions which were to remain unaltered for the whole of Three Litre production. A seven bearing crankshaft was carried in thin wall bearings in a deep cast iron crankcase, integral with the block. Valve gear was conventional pushrod overhead, driven by chain from the rear in time honoured Alvis fashion, with light springs holding the pushrods in permanent contact with the rockers in the interest of silence.

1953 TB 21 AP Metalcraft 2-seater sports

A single Solex downdraught carburettor was fitted, but two exhaust manifolds were used, feeding into a completely dual system, right to the small bore twin tailpipes. Output was said to be 90 bhp, which cynics would point out was only a marginal increase over the pre-war Speed 20 and 5 bhp less than the Silver Crest, both of rather smaller displacement. It was, however, a notably smooth and silent unit with great mid-range torque. Standard coachwork was a four door sunroof saloon, again by Mulliner, and a very neat 2-door drophead from Tickford. The saloon looked rather dated, but Mulliners moved to cast aluminium for door frames and pillars, rendering these bodies surprisingly light and very strong.

1953 TA 21 Graber saloon

The instruments reverted to separate dials, white on black, which must have pleased the traditionalists. Maximum speed was some 90 mph. Fairly early on in the production run twin SU carburettors became standard, many earlier cars had them retro fitted. It was said that they improved economy and idling characteristics. The fitting of specialist coachwork was very rare by now, but some chassis went to Hermann Graber in Switzerland who fitted bespoke coachwork of his own design, much more up to date than the British offerings. Graber was to play a big part in the Alvis story later on. A 2-seater sports version, the TB 21, was offered in 1951-3.

1955 TC 21/100 Tickford DHC

This was the TB 14 body adapted to fit the TA 21 chassis, but with the æsthetics improved out of all recognition by fitting the normal Alvis radiator. About 20 were made, some with a large single SU carburettor, others with twins. The TA 21 became the TC 21 in 1953, the main difference being the fitting of lighter, chromium plated, window frames and concealed door hinges. Some had a higher axle ratio and increased compression as well. Sales were falling, however, until it occurred to someone that this was now a car capable of 100 mph. Thus the TC 21 became the TC 21/100, often called the Grey Lady, standardising the high compression cylinder head and the high ratio axle.

1954 TC 21/100 Mulliner saloon

Many had the fifties equivalents of spoilers and alloy wheels, in the form of louvres and air scoops on the bonnet, and knock-on wire wheels. Power was up to 100 bhp and speed to a fraction over 100 mph. A hundred miles an hour was still quite exceptional for a production car at the time, so the model attracted favourable publicity, and orders rose accordingly, extending the life of this otherwise dated looking car. Alvis had experienced persistent body supply problems since the war as one by one the contract body makers were swallowed up by other manufacturers. With Mulliners taken over by Standard, and Tickford by Aston Martin, TC 21/100 production came to an end.

1954 TC 21/100 Graber DHC

It was realised that a more modern body design was essential, and it was believed that Hermann Graber might provide the answer until radical new designs under development reached production. Accordingly two prototypes and the necessary jigs were bought from Switzerland. Production was placed in the hands of bus body makers Willowbrook, and around 16 very elegant 2 door cars were made under the designation TC 108G. Although the cars were much discussed and reviewed very favourably, sales were poor because of the very high price, and there were persistent body quality problems. A total of some 2,100 of the TA - TC 21, TC 21/100 and TC 108G were made.

1957 TC108G Willowbrook saloon

With the Car Division consistently losing money, the radical new designs by Alec Issigonis proving impossible to put into production and the sales failure of the TC 108G, the future looked bleak indeed for the Alvis car, especially as the Aero Engine and Military Vehicle divisions were doing very well, generating excellent profits. The heyday of Alvis as a car maker had been before the war and its survival into the 1950s was a mere swansong. Few would have believed that nearly ten years of successful development and production lay ahead for the Three Litre.

1957 TC108G Graber saloon