Audi Unveils Recreated Auto Union Lucca Record Car
This car makes a statement. The Auto Union Lucca embodies the technical innovation the four rings achieved in the 1930s. Audi Tradition has recreated this spectacular record-breaking car. It will unveil it for the first time in early May in the Italian city of Lucca, a fitting choice of location. On 15 February 1935, the car set a widely acclaimed flying-start mile record on a straight section of the autostrada near Lucca, achieving a calculated average speed of 320.267 km/h and a measured top speed of 326.975 km/h. Audi Tradition completed the Rennlimousine, a period term meaning "racing sedan", in spring 2026, and the car now joins the legendary Silver Arrows in AUDI AG's historic vehicle collection.
The 1930s brought an international race to set speed records. Speed meant far more than a mundane measurement: the media and the public followed and celebrated Grand Prix races and constant record-breaking almost obsessively. Over the years, Germany became the scene of fierce competition among brands, drivers, and technologies, pitting the star against the four rings, Caracciola and von Brauchitsch against Stuck and Rosemeyer, and front-engine cars against mid-engine cars. Auto Union AG, formed in 1932 through a merger of Audi, DKW, Horch, and Wanderer, entered its first Grand Prix season under the new 750-kilogram formula in 1934 with the 295 PS Auto Union Type A. That same year, the brand led the way in speed records: Auto Union set three world records on 6 March and five more on 20 October, all in a car driven by the experienced racing driver and hill-climb specialist Hans Stuck.
Daimler-Benz AG felt the pressure and stepped up its game. Rudolf Caracciola matched Stuck's record and, in late October 1934, set several international records on the highway near Gyón, Hungary, driving a specially built record-attempt car. Among other records, he reached an average speed of 316.592 km/h over a flying-start mile, setting a mark that Auto Union would later beat. Race engineers and mechanics at Auto Union faced a demanding winter, since they were already planning the next record attempts for early 1935 and needed to raise their racing car's performance. Building on the vehicle used to set the October records, the team's experts first developed a wind tunnel model. They tested this extensively, first as an open version, then with a closed cockpit for improved aerodynamics.
Auto Union's racing division incorporated findings from the wind tunnel at the Berlin-Adlershof Aeronautical Research Institute into the design of what would later become the record-breaking car, achieving what "Automobilrevue" called, at the time, "a first in European racing car construction."
Workers finely sanded the body, coated it with clear lacquer, and fitted the spoked wheels with wheel covers. Two circular openings at the rear served as fresh-air intakes for the carburettor, while the exhaust pipes pointed upward and were grouped into two outlets on each side. The car already carried a 16-cylinder engine from the 1935 season, with displacement increased to approximately 5 litres. However, this early version, producing 343 PS, did not quite match the 375 PS the team achieved later in 1935. The chassis and suspension still matched those of the 1934 racing car, while the elongated, aerodynamic silhouette, with its fin-like rear end and teardrop-shaped wheel arches, clearly set the car apart from its racing counterparts of the previous season. These changes, though primarily technical and functional, gave the car a speed-driven aesthetic that made the Rennlimousine, as the press dubbed it, truly one of a kind.
The record-breaking route ran from Gyón in Hungary to Milan to Lucca. After just a few weeks of development work, Auto Union's racing division finished the car in its Zwickau workshop by December 1934. The team test-drove it for the first time on Berlin's Avus circuit on 17 December, and at the end of January 1935 made the decision: the record attempt would take place in Hungary, on the very same track near Gyón where Caracciola had set the class record for a flying-start mile in a Mercedes the previous year. Auto Union arranged everything with the Hungarian Automobile Club, and the high-performance record contender arrived in Budapest on 4 February 1935. The team set off the next day for the route roughly 40 kilometres further south, but the weather rapidly deteriorated. Even so, the team carried out two test runs on 5 February. During the second run, the exhaust pipe burnt through, forcing the team to suspend testing. Because of the unprorganisersweather, race organisers decided to continue the record attempts south of Milan. Conditions proved far from ideal there too, since snow covered the planned route, so Auto Union headed even further south and finally found a suitable stretch on the Florence-Viareggio road between Pescia and Altopascio, near the city of Lucca.
This section of the autostrada suited record attempts perfectly: level, with a high-grip surface, eight metres wide, and virtually straight for around five kilometres. The team began the first test drives on 14 February 1935. They trialled various vehicle configurations, adjusted details such as the radiator grille, and analysed the door covers and the data closely. The next morning at 9 am, the car returned to the track near Lucca, this time with Hans Stuck at the wheel. Word had already spread that something big was in the works. "Automobilrevue" wrote: "Auto Union's new single-seater racing car, with its streamlined body made entirely of light metal, caused quite a stir among the many prominent figures from the world of Italian sports who had travelled to Lucca for the event. (…) Thousands of spectators watched the test runs." Official timekeepers were also on hand: the independent chronometrists of the era used state-of-the-art chronometers equipped with electrically triggered photocells.
Stuck made several attempts, and the team made further adjustments to the Rennlimousine. After sealing the front of the radiator, covering the grille except for a small opening, and further refining the aerodynamics, the team finally achieved its ambitious goal. Over two average runs, Stuck set the flying-start mile record in International Class C at an average speed of 320.267 km/h. The measuring devices also recorded a time of just 11.01 seconds for a section of the return run in "Run 3 Stuck II," corresponding to a blistering kilometre speed of exactly 326.975 km/h, making the car the fastest road-racing car in the world.
Auto Union naturally wanted to broadcast the spectacular display of speed near Lucca to the world immediately, giving the brand yet another edge over the Silver Arrows from Stuttgart in their hotly contested battle for prestige. Almost simultaneously with the successful record attempt in Lucca, Auto Union unveiled a virtually identical version of the record-breaking car at the International Motor Show in Berlin, held from 14 to 24 February. The main difference from the Lucca model was its larger grille. Since recognised had not yet recognised the mile record, the promotional poster created for the trade show, alongside a list of every world and class record Auto Union brands had achieved to date, featured the Lucca car as the fastest road racing car in the world, citing its top speed of 326.975 km/h.
On the racetrack in late May 1935 at Berlin's Avus circuit, Auto Union proved that success in motorsport demands constant proof, so the racing division immediately analysed the data collected in Lucca to continue developing and refining the vehicle. The modified Lucca car made its next appearance just a few months after setting the record in Italy. This time, alongside its Berlin counterpart, organisers held the fifth International Avus Race in Berlin on 26 May 1935. Since this was a non-formula race and the 750kg weight limit did not apply, Auto Union fielded not only two Grand Prix cars but also the two heavier Rennlimousinen, with a documented starting weight, including the driver, of 1,030kg. Hans Stuck and the Italian Achille Varzi drove the Grand Prix cars, while Prince Hermann zu Leiningen, a member of the Auto Union team since early 1934, drove the former Lucca car under starting number 3. Bernd Rosemeyer, a young driver signed for the 1935 season, drove the second Rennlimousine, numbered 4, which had appeared at the Berlin motor show and now carried a larger radiator grille for the Avus race. Rosemeyer reached an impressive 290 km/h in practice and therefore started alongside Stuck on the front row in the first heat. But as he accelerated out of the north curve, his car's right rear tyre burst. Rosemeyer managed to bring the car under control and rolled to the side of the track, bringing his very first circuit race for Auto Union to an early end. In the second heat, Prince zu Leiningen started from the second row in his Rennlimousine, the technically enhanced record-breaking car from Lucca, driving alongside Mercedes driver Rudolf Caracciola, who carried starting number 5. Achille Varzi in car 2 and Manfred von Brauchitsch in car 6 started at the front. At first, the two Auto Union cars battled for the lead, with Rudolf Caracciola at the wheel. However, Auto Union ultimately had to cede victory to its competitors from Stuttgart, since Hermann zu Leiningen's Rennlimousine could not withstand the constant strain and he, too, retired his car during the heats due to a damaged coolant line.
The Auto Union Lucca embodies the pursuit of "higher, faster, further." The 1930s show just how fast-paced motorsport can be and how many ups and downs, successes, and dramatic moments it offers: the Lucca car set a speed record in Italy in mid-February 1935, yet by the end of May, neither Rennlimousine reached the finish line of the Avus race in Berlin. At the same time, both the Auto Union Lucca and its Avus variant gave the Auto Union racing team valuable insights and played an important role in the history of the four rings inthe 1930s motorsport, as Stefan Trauf, Head of Audi Tradition, explains: "Audi does not yet have any Auto Union racing or record-attempt cars from the early Grand Prix era in its historic vehicle collection. With the Auto Union Lucca, we are adding a highly evocative member of the Silver Arrow family to the AUDI AG collection. The record-breaking car from Lucca is an impressive demonstration of the role of engineering: setting new standards, breaking new ground, and continually pushing the boundaries of what's possible. The car is a testament to the four rings' technical innovation and demonstrates how 'Vorsprung durch Technik' was achieved in the 1930s. To me, the Auto Union Lucca is a masterpiece of engineering, tuned for high speeds and maximum performance, yet at the same time a beautiful car; in my view, this combination is unique."
Audi commissioned Crosthwaite & Gardiner to recreate the Auto Union Lucca based on historical photographs and other archival documents. After spending just over three years on the project, the British restoration specialists completed it in early 2026. Artisans handcrafted every component especially for this model; alongside the technical work, producing the streamlined bodywork, such as the cockpit canopy and the tapered tail, proved particularly labour-intensive. The hard work paid off: at the end of April, engineers measured a drag coefficient of 0.43 for the record-breaking car in the Audi wind tunnel.
Timo Witt served as project manager for the construction of the Auto Union Lucca. He has led the historic vehicle collection at Audi Tradition since 2015 and previously spent more than ten years working as a motorsport engineer. Witt says: "I'm impressed by the agility and speed with which they responded to the competition back then, in the technical realm, in organisational matters and in organisational matters: when the weather takes a turn, the whole team moves on without hesitation. Without this high degree of flexibility or the ability to adapt to new situations at lightning speed, the record-breaking drive in Lucca would not have been possible." Timo Witt also shares some fascinating details about the vehicle's construction: "Of course, we recreated the car as authentically as possible, but at the same time, issues such as maximising durability and maximising efficiency in the project's implementation were also important to us." He illustrates this with two examples: Audi Tradition fitted the Lucca with the 16-cylinder engine from the Auto Union Type C, because its 6-litre engine looks visually indistinguishable from a 5-litre engine, making the engines interchangeable within the Silver Arrow family. The Auto Union Lucca also carries several modifications the team implemented for the Avus race in Berlin in May 1935, such as the ventilation system. Timo Witt explains: "We made these changes to the Auto Union Lucca because, otherwise, the vehicle would have been subjected to excessive thermal stress during our upcoming demonstration runs." With minor modifications to the radiator or body panels, the team can convert the Auto Union Lucca into the Avus.
Whether in Lucca or Avus configuration, the Auto Union Lucca embodies, like almost no other model in the Auto Union lineup of racing and record-attempt cars, the deeply emotional fusion of maximum performance and elegant lines. After its unveiling in Lucca, Italy, the Rennlimousine will make its first public appearance in motion at the Goodwood Festival of Speed, running from 9 to 12 July.
