Grand Prix Sunbeams 1921, 1922 TT

[10] The highly evolved Experimental Departments in Wolverhampton and Suresnes cooperated on the meticulous development and construction of these fine wholly hand-crafted machines.

[11] Racing program was extensive; tailor-made alternative lightweight bodies, specific axle ratios and engines to suit each event were formed.

to the highest echelons of the sport, with numerous successes still legendary today, the costly racing policy may have ultimately led to the demise of the once mighty S.T.D.

"Coatalen produced the world's first twin-cam Six for the 1916 Indianapolis 500"[42] an Ernest Henry prewar Peugeot type in-line six cylinder 81.5x157 mm, capacity 4,914 cc.

Two cast blocks of three; twin overhead camshafts driven by a vertical shaft and gears from the front of the engine; four valve per cylinder (24 in total), 60 degrees included angle.

In the careful hands of J Christiaens who suggested their construction, his car regularly finished 'in the Money' winning large prizes including $3,000 (4th) in that year's Indianapolis 300-Mile.

Sunbeam chassis;[46] Josef Christiaens was killed demonstrating one of the cars[46] at Wolverhampton and they were subsequently entered at that year's Indianapolis 500 for J Chassagne and Dario Resta.

Fuel feed by pressure from 30-gallon copper bolster tank at rear was used in the Isle of Man Tourist Trophy[1] and the Coppa Florio; other configurations in other events.

Subtle changes to ratios were made according to the topography of each speed event:[57] Dry sump lubrication employing two gear-type oil pump (pressure and scavenge).

[34] Water pump mounted on the front of the timing gear case delivering into a gallery pipe along the near side of the engine with eight separate feeds into the cylinder block below the exhaust ports.

[34] Brake cables, running over phosphor bronze pulleys,[58] adjustable by ratchets below a sideways hinged 6"x8" trap door in the floor in front of the riding mechanic.

[54][60][62] Wheels: Tyres:[63] The lightweight all aluminum body consisted of a bonnet riveted to reinforcing copper and brass straps, scuttle on angled steel, seats tub and tail.

[65] The side blisters on the bonnet were modified to accommodate different carburettor configurations;[17][23][66] a hatch on scuttle was formed when a 1916 4.9 L engine was used;[67] alternative tails and radiators were used as needed.

envisaged seven entries but only weeks before the event the cars were not ready and an attempt to withdraw was made; this met with resistance from the designated pilots and after considerable effort by the S.T.D.

[81] The road circuit was badly cut out and covered with large sharp stones one of which knocked Segrave's riding mechanic Jules Moriceau unconscious for the whole of half a lap.

[82] The four cars were repatriated to Wolverhampton England; the two Talbot were fitted with Sunbeam radiators and entered at the 1921 September 9 Shelsley Walsh – the premium annual hill-climb in the United Kingdom.

[28] The '1,500 Trophy' attracted three blue Talbot-Darracqs which were smaller version of the Sunbeams with one cylinder block instead of the two that made the bigger cars;[99] three Crossley-Bugattis came from France for the first time; a peacock-blue Enfield-Allday driven by A C Bertelli; Hillman and three Aston Martin though only one ('Bunny') reached the start line.

[101] The event was held in appalling weather, wind, heavy rain and mist reducing visibility to less than 20 yards; later the winner Chassagne described the conditions as "a nightmare in sea of mud".

[101] The calcium chloride, which was used on the circuit as dust-laying compound, in the rain, made the roads muddy and greasy and caused burning irritation to driver's eyes.

[103] Sunbeam I race no.1 for K Lee Guinness (riding mechanic Bill Perkins) winner of the previous Tourist Trophy event in 1914 did not start due to slipped clutch.

[107][108] Of the ten voiturette starting the event, six completed; Sir Algernon Guinness with Talbot Darracq I no.24 reaching 90 mph on the Sulby straight and winning a 1–2 (with Divo 2nd) for S.T.D.

[123][124] Chassis no.4 with a 4.9 L engine was purchased by Malcolm Campbell, painted blue, liveried 'Blue Bird' and proceeded to successfully take part in numerous Brooklands events in several hands over many years.

chassis 4.9 L car appeared in 1922 for an attempt on the 24 hour record and subsequently used by Dario Resta 1924 March 29 at Kop Hill Climb where it did second fastest time of day (29.2sec).

[10] Engine types (3-litre and 4.9-litre), brake system, body configurations, fuel tanks and axle ratios were also changed from one event to another making the essentially identical cars appear potentially different.

Research of the history of individual cars was predominantly carried out and published by Dick Messenger, Peter Hull, Graham Vercoe and George Begg.

1925 1926 1928 1929 1931 1932 1933 1934 1935 1940 John W Burnand with Rolls-Royce 14.5 – litre V12 Falcon engine 1950s Soon after obtaining the best European result in the 1921 Indianapolis 500, this car took part in that year's French Grand Prix.

It remained largely unused until purchased by Sunbeam expert Anthony S. Heal who had Len Gibbs in 1946 comprehensively rebuild the car and paint it British Racing Green; non-original rigid pattern steering wheel fitted.

In the 1960s it passed to John T Panks (Rootes General Manager) and was restored in New York; a pair of Solexes replaced the original Claudel Hobson carburettors.

Purchased by Bentley enthusiast Guy Shoesmith in 1968 who commissioned Donald McKenzie to carry out bare chassis full mechanical restoration; new dashboard using the original instruments was made.

Works, it spent most of its life in a few long-term ownerships in New Zealand where it remained an effective, iconic and well-liked racing car both before and after the War; displayed in a motor museum for many years before it was recommissioned and repatriated to the UK.