Finished in spring 2026, the project returns a missing piece of early Grand Prix engineering to Audi’s historic Silver Arrow collection. The car, known in its day as a Rennlimousine, or racing sedan, was rebuilt over more than three years by British restoration specialists Crosthwaite & Gardiner.
The original Auto Union Lucca was born during an intense period of record chasing in the winter of 1934 and 1935, when Auto Union and Daimler-Benz were pushing each other toward higher speeds. Auto Union’s engineers started from the lessons of an earlier record-attempt car, then refined the concept through wind tunnel testing at the Berlin-Adlershof Aeronautical Research Institute. Both open and closed-cockpit layouts were studied before the final shape was chosen.
That shape remains dramatic almost a century later. The car has a long silver body stretched tightly over the chassis, covered spoked wheels, teardrop-shaped wheel arches, a narrow tail fin, and two round air intakes behind the cockpit. Grouped exhaust outlets run along the sides, giving the machine a raw, technical presence. It looks sculptural, but nothing on it is decorative. Every surface was tied to airflow, cooling, pressure, or stability.
The record attempt was originally planned for the highway near Gyón in Hungary, where Mercedes had set a flying-start mile record in late 1934.
Bad weather forced Auto Union to move south. The team first looked toward Milan, then had to continue farther when snow covered the intended route. Eventually, they found a suitable stretch between Pescia and Altopascio, not far from Lucca.
The road was flat, grippy, roughly eight meters wide, and straight for about five kilometers. On February 14, 1935, the team began practice runs, changing details such as the radiator grille, wheel covers, and aerodynamic trim. The next morning, driver Hans Stuck returned to the course. Official timekeepers recorded the attempts using electrically triggered photocells.
The fastest configuration came after the front radiator opening was almost completely closed, leaving only a small slot for cooling. Across two averaged runs, Stuck set a flying-start mile record in International Class C at 320.267 km/h. On part of the return run, the instruments showed 326.975 km/h. That figure gave the Auto Union Lucca its place in history as the fastest road racing car in the world at the time.
Its significance goes beyond the number. The Lucca shows how quickly race engineering was changing in the 1930s, as aerodynamics, engine development, bodywork, and brand image became part of the same technical race. The car’s elegance comes from that pressure. Its lines are beautiful because they are working.
For the reconstruction, Audi Tradition relied on archival photographs and documents. The bodywork was one of the most demanding parts of the project. The compact cockpit canopy, tapered tail, and other model-specific components were shaped by hand.
Tested in Audi’s wind tunnel, the recreated car recorded a drag coefficient of 0.43.
The new Auto Union Lucca uses a 16-cylinder engine from the Auto Union Type C, with a 6.0-liter displacement and 520 PS. Audi Tradition chose this unit because it is visually close to the 5.0-liter engine used in the original car, while also allowing the reconstruction to run as part of the broader Silver Arrow collection. The vehicle also includes several Avus-race-inspired modifications, including ventilation updates intended to help manage heat during future demonstration runs.