At his death in 1933, without sons of his own, he was succeeded by his next surviving male relative, his paternal uncle Sir Alexander Russell Birkin, 4th Baronet (died 1942).

Birkin joined the Royal Flying Corps during World War I and gained the rank of Lieutenant in the service of the 108th (Norfolk and Suffolk Yeomanry) Field Brigade, serving in Palestine where he contracted malaria, a disease from which he would suffer for the rest of his life.

With technical help from Clive Gallop and supercharger specialist Amherst Villiers, and with Dorothy Paget financing the project after his own money had run out, Birkin rebuilt the car at the engineering works he had set up for the purpose at Welwyn Garden City in Hertfordshire.

Adding a huge Roots-type supercharger ("blower") in front of the radiator driven straight from the crankshaft gave the car a unique appearance.

Birkin's courage and fearless driving, in particular his selflessly harrying Caracciola into submission, are regarded as embodying the true spirit of the Vintage Racing era.

Back in 1925 the energetic motor sports enthusiast Eugène Azemar, who was involved with the Tourist Board in Saint-Gaudens in southern France, succeeded in persuading the Automobile Club du Midi to arrange a Grand Prix race in the region.

The new date meant that the Italian teams were unable to attend, leaving it to be mostly an internal French affair with sixteen Bugattis, two Peugeots and a Delage among the twenty five starters.

Among the top Bugatti drivers were Louis Chiron, Marcel Lehoux, Count Stanislas Czaikowski, Jean-Pierre Wimille, Philippe Étancelin and William Grover-Williams.

A curiosity in the largely single-seat entry list was Tim Birkin's blower Bentley touring car, stripped down to racing trim, with headlights and mudguards removed.

Guy Bouriat took an early lead, followed by Williams, Zanelli, Czaikowski and Étancelin, with Birkin as first non-Bugatti driver, in sixth place.

The car (nicknamed the Brooklands Battleship) had been re-bodied with a single shell by Reid Railton after its lightweight fabric two seater body had caught fire in the 1929 500-mile race due to a cracked exhaust.

Birkin kept his motor workshop going by entering into a partnership with Mike Couper and developing a business specialising in tuning high performance cars.

In addition, an "electric model Brooklands" – an elaborate miniature racetrack game with motorized cars running on single rails – was manufactured at the works.

In 1931 he won Le Mans with Earl Howe in an Alfa Romeo, even receiving a telegram from Mussolini congratulating him on his "win for Italy".

During his pit stop Birkin burnt his arm badly against the hot exhaust pipe while picking up a cigarette lighter.

It was probably a combination of both that proved fatal, as Birkin died at Countess Carnavon Nursing Home in London 22 June 1933,[citation needed] aged thirty-six.

Cobb drove a ten and a half-litre Delage, once holder of the land speed record, and Birkin his four and a half supercharged Bentley, the 'Brooklands Battleship.'

(key) (Races in bold indicate pole position) Sir Tim Birkin is featured in this compilation film of 1920's and 30s footage on YouTube.