Fiat Mefistofele: The Last Public-Road Land Speed Record

By 1923, breaking 200 hp meant raiding aviation technology — which is exactly what British engineer and racing driver Ernest Eldridge did. He bought a 1908 Fiat SB4 chassis and stripped out its original engine, replacing it with a colossal 21.7-liter Fiat A.12 aircraft engine producing roughly 320 hp. The unmuffled exhaust produced such tremendous noise and smoke that the French press nicknamed the car “Mefistofele” — Mephistopheles, after the demon.

Eldridge’s target was the World Land Speed Record, then held at 199.70 km/h. On July 12, 1924, he took the Mefistofele to the public Route d’Orléans at Arpajon, France, going head-to-head with French rival René Thomas, who arrived in a more modern Delage V12 nicknamed “La Torpille.” Despite Thomas’s car boasting nearly as much power from roughly half the displacement, Eldridge’s brute-force Fiat prevailed, reaching an official 234.98 km/h (146 mph) and setting a new world record. It stood for only 32 days — but the run holds a unique distinction: it remains the last World Land Speed Record ever set on a public road, before the pursuit moved permanently to closed circuits and dry lake beds.

The car survives today, fully restored and running. In 1969, Fiat chairman Giovanni Agnelli purchased it from Eldridge’s heirs and brought it home to Italy, where it now resides in the Centro Storico Fiat collection in Turin — a rare, hand-built glimpse into the earliest era of land speed racing.