Romeo 8C 2900 – 1939 Alfa Romeo 8C 2900 clocked to average at Brooklands Speedway (41 made)'' Fastest pre-war vehicle – Railton Mobil Special – 2-SC Napier Lion V-12 – – Driver John Cobb on 23 August 1939 at the Bonneville Salt Flats Longest pre-war production – – 1933–35 (for the 1934–35 model years) Cadillac V-16 Longest pre-war limited production – 1927–33 Bugatti Royale Longest pre-war production wheelbase – – 1933–37 (for the 1934–37 model years) Cadillac V-16 Longest pre-war limited production wheelbase – 1927 Bugatti Royale Prototype Longest pre-war Production convertible – (29 produced) – 1933–1935 (for the 1934–35 model years) Cadillac V-16 Longest pre-war Production coupe – (20 produced) – 1933–1935 (for the 1934–35 model years) Cadillac V-16 Longest pre-war Limited production convertible – – 1932 Bugatti Royale Weinberger Longest pre-war Limited production coupe – – 1931 Bugatti Royale Kellner Widest pre-war – 1938–43 Mercedes-Benz 770 W150 (armoured) Widest pre-war front track – – 1938–43 Mercedes-Benz 770 W150 Widest pre-war rear track – – 1938–43 Mercedes-Benz 770 W150 Tallest pre-war production car – – 1904–09 Fiat 60 HP Heaviest pre-war curb weight – – 1938–43 Mercedes-Benz 770 W150 (armoured) Largest pre-war limited production car inline-four engine 1911 Fiat S76 Record Largest pre-war straight-6 – – 1920-28 Reanault 40CV Largest pre-war limited production straight-8 – – 1927 Bugatti Royale Largest pre-war V8 – – 1910–12 De Dion-Bouton Largest pre-war V12 – – 1912 Pierce-Arrow Largest pre-war V16 – – 1930–33 (for the 1931–33 model years) Marmon Series 16 See also List of largest machines (including land vehicles) Units of measurement International System of Units United States customary units Imperial units Power Torque Mass References Superlatives Automobiles