1923 Grand Prix season
Manufacturer Model Engine Power Output Max . Speed ( kph ) Dry Weight ( kg )
Fiat 805-405 FIAT 1979cc S6 supercharged 130 bhp 220 680
Alfa Romeo GPR ( P1 ) Alfa Romeo 1990cc S6 95 bhp 180 850
Diatto Tipo 20 S Diatto 1997cc S4 75 bhp 155 700
Bugatti Type 32 Bugatti 1991cc S8 100 bhp 190 660
Voisin C6 Laboratoire Voisin 1978cc S6 90 bhp 175 710
Sunbeam Sunbeam 1988cc S6 108 bhp 180 675
Mercedes M7294 Mercedes 1990cc S4 supercharged 120 bhp 180 750
Benz RH Tropfenwagen Benz 1998cc S6 95 bhp 185 745
Miller 122 Miller 1978cc S8 120 bhp 186 850
Regulations and Technical
The regulations set up by the AIACR ( forerunner of the FIA ) in 1922 for Grand Prix races remained . The maximum engine limit was 2.0-litres and the minimum weight 650kg . The cars were 2-seaters and the weight of the driver and mechanic had to be at least 120kg . [ 7 ] The pre-war ban on forced induction had not been re-applied when racing resumed and several manufacturers were now working on the loophole for more power . [ 8 ] Not for the last time in Grand Prix racing would technical innovation outmanoeuvre technical regulation . In the United States Carl G. Fisher , the driving force behind the Indianapolis 500 , announced his intention to retire . Before he left , however , he pressured the American Automobile Association ( AAA ) to change their regulations to align with the European formula . The 183 cu in ( 3-litre ) engine limit was therefore reduced to 122 cu in ( 2-litre ) with a view of attracting European competition to keep the 500 race 's future secure and to stop forestall a technology gap . [ 7 ] [ 9 ] In recognition of this , the Indianapolis 500 was also designated a Grand Épreuve by the AIACR . The AAA also removed the requirement to carry a riding mechanic while racing . [ 9 ] Miller 122 : 1922 ( left ) & 1923 ( right ) versions ) Forced to develop new engines , the leading companies took different strategies . The Frontenac name disappeared : Louis Chevrolet was already under financial pressure and was soon driven under . Fred Duesenberg designed his first double-overhead cam engine . Harry Miller saw an opportunity with the smaller engine and passenger restrictions lifted to build a lightweight single-seater that was a pencil-thin racer tailor-made for the high-speed boardwalk ovals . [ 9 ] In contrast , the Targa Florio regulations remained open to any-sized cars . However the distinction between Production and Racing cars was removed with just the six classes based on engine-capacity . [ 10 ] Following the success to Fiat the previous year , both Alfa Romeo and Sunbeam developed 6-cylinder engines . The non-competitiveness of the last Sunbeam was the end of an illustrious career for designer Ernest Henry . He was replaced by Vincenzo Bertarione from Fiat . His first design bore a strong resemblance to the 1922 Fiat and the contemporary press named it the “ English Fiat ” . [ 11 ] [ 12 ] Pietro Bordino in his Fiat 805-405 Fiat , however , had already moved on . The design team of Guido Fornaca introduced the new 805 model . Now with an 8-cylinder 2-litre engine augmented by a Wittig supercharger that gave it 130 bhp , capable of up to 220 kph [ 11 ] – easily 30-40 kph faster than the competition . Unlike the Mercedes version , the Fiat supercharger ran continually . [ 12 ] The Bugatti Type 32 was a remarkable design departure from the previous Bugatti cars . Its distinctive aerodynamic shape was modelled on an aeroplane wing , earning it the nickname le tank de tours . The car 's very short wheelbase and long 8-cylinder engine meant a regular gearbox could not be fitted so Bugatti used a 3-speed unit . An innovative front brake system left the driver with no brake pedal and had to use an on-board lever . Finally , with no firewall between the engine and the crew , meant it was very cramped , hot and exhausting with the drivers complaining of poor visibility . [ 13 ] Ernest Friderich practicing in the Bugatti Type 32 for the French GP Gabriel Voisin drew upon his previous experience in aircraft design for his Grand Prix car . Like the Bugatti , it also featured harsh enclosed aluminium bodywork on a semi-monocoque timber chassis . However , the car was stymied by the underpowered sleeve-valve engine . [ 14 ] [ 15 ] Delage went down a completely different track with a standard chassis but fitted with a twin-cam V12 engine designed by Charles Planchon . [ 16 ] [ 15 ] The Benz-Tropfenwagen was ground-breaking in another way : as well as a teardrop-shaped body , the engine was mounted just ahead of the rear-axle . This mid-engine car foreshadowed the GP cars seen over 30 years later . It also employed independent suspension on all four wheels which was another first for a Grand Prix car . [ 14 ]
The 1923 Grand Prix season saw Grand Prix motor racing in Europe. For the first time, the Indianapolis 500 was also designated a Grand Épreuve by the International Sporting Commission of the AIACR. The French Grand Prix was held in Tours. The Italian Grand Prix (which was also the European Grand Prix) was held at Monza. Spain entered the Grand Prix circus with the Spanish Grand Prix at Sitges-Terramar and the first San Sebastián Grand Prix at Lasarte.