Car Restoration Projects

Audi Tradition has unveiled its latest resto/replica initiative: the Auto Union Lucca record-breaking car of 1935. This aluminium-bodied streamliner joins the Typ 52 and Silver Arrows cars that have been recreated by Crosthwaite & Gardiner, under Audi’s aegis.

Audi Tradition unveiled its latest recreation in early May 2026 in – aptly – the Italian city of Lucca. This newly recreated Rennlimousine was scheduled to appear at the Goodwood Festival of Speed in July 2026 and make its way up the famed hillclimb track. Let’s start with a look at Auto Union’s racing heritage and this one-off machine’s history:

The 1930s was a time of international obsession with setting  motoring speed and endurance records. Grand Prix races and speed records were followed and celebrated by the media and the public. 

With support from a Nazi regime keen to promote German technological superiority, the Mercedes-Benz star and Auto Union’s  four rings were in constant competition from 1934 until 1939: Caracciola and von Brauchitsch versus Stuck and Rosemeyer; front-engine versus mid- engine. 

Auto Union AG, founded in 1932 by a merger of Audi, DKW, Horch and Wanderer, entered its first Grand Prix season under the new 750kg formula in 1934, with the 295PS Auto Union Type A. That same year, it led the way in setting speed records: three world records on 6th March and five more on 20th October, in a car driven by the experienced racing driver and hill climb specialist Hans Stuck. 

Daimler-Benz AG was therefore put under pressure and stepped up its game: Rudolf Caracciola tied Stuck’s record and, in late October 1934, set several international records on a highway near Gyón, Hungary, in a specially built record-attempt car. Caracciola maintained an average speed of 316.59 km/h over a mile, from a flying start. 

In late 1934 Auto Union prepared its next record attempts: firstly by using a model car in the Berlin- Adlershof Aeronautical Research Institute wind tunnel. Tests began with an open version, then with a closed cockpit, for improved aerodynamics. 

After just a few weeks of development work, the car in the workshop of Auto Union’s racing division in Zwickau was finished by December 1934. When it was released, the 1935 car was coined Rennlimousine by the press.

The chassis and suspension were carried over from the 1934 racing car, but the 1935 edition’s elongated, aerodynamic silhouette, with its fin-like rear end, teardrop-shaped wheel arches and spoked wheels fitted with flush covers made it stand out. 

The hand-beaten aluminium bodywork was finely sanded and coated with clear lacquer, to reduce wind resistance. Two circular openings at the rear served as engine air intakes and the paired exhaust pipes pointed upward. (Subsequently, a drag coefficient of 0.43 was measured on the 2026 Lucca car in the Audi wind tunnel.)

Power came from the 1935-year 16-cylinder engine, whose displacement had been increased to five litres, with an initial output of 343PS: later 375PS.

The record attempt

The car was test-driven for the first time on Berlin’s Avus circuit, on 17th December, 1934. By the end of January 1935, the decision was made to attempt the record in Hungary: on the very same track near Gyón where Caracciola set the class record for a flying-start-mile, in a Mercedes-Benz, the previous year. 

The record contender arrived in Budapest on 4th February, 1935 and  two test runs were carried out the next day, despite poor weather. On the second run, the exhaust pipe burnt through and the tests were suspended. 

Due to worsening weather, the venue was changed to Italy; south of Milan, where conditions weren’t any better, so Auto Union headed even further south. A suitable stretch of highway was found on the Florence-Viareggio Road, between Pescia and Altopascio, near the city of Lucca. 

This section of the autostrada was eight meters wide, level, with a high-grip surface and virtually straight as an arrow for around five kilometres. 

The test drives began on 14th February, 1935 and the record attempt was set for the following day, with Hans Stuck at the wheel.

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 traveled to Lucca for the event. Thousands of spectators watched the test runs.” 

Stuck made several attempts, during which some adjustments were made to the Rennlimousine, including partially sealing the front of the radiator.

Finally, over two averaged runs, the flying-start-mile record in International Class C was set at an average speed of 320.267km/h, with a blistering speed over one kilometre of exactly 326.975km/h – making the car the ‘fastest road racing car in the world’. 

Since success in motorsport must be proved again and again, the racing division in Zwickau immediately analysed the data collected in Lucca, to continue developing and optimising the vehicle. 

The modified Lucca car made its next appearance just a few months after setting the record in Italy, accompanied by a second – Avus – car. On 26th May, 1935, the fifth International Avus Race was held in Berlin. Because this was a non-formula race and the 750kg weight limit didn’t apply, Auto Union fielded two Grand Prix cars and also the two heavier Rennlimousinen that tipped scales at 1030kg. 

Hans Stuck and the Italian Achille Varzi drove the Grand Prix cars; the driver of the former Lucca car was Prince Hermann zu Leiningen and Bernd Rosemeyer, a young driver signed for the 1935 season, drove the second Rennlimousine. 

Rosemeyer reached an impressive 290km/h in practice and 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 tire burst. Rosemeyer managed to get the car under control, but his first circuit race for Auto Union came to an early end. 

In the second heat, Prince zu Leiningen retired his car after a coolant hose failure. 

Despite these failures in cars that were never intended for circuit races, the Rennlimousinen provided the Auto Union racing team with valuable insights and played an important role in the history of the four rings in motorsport in the 1930s.

The recreation

In explaining why Audi commissioned the Lucca replica, Stefan Trauf, Head of Audi Tradition, said: “Audi did not 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 technical innovation of the four rings and shows 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 had the Auto Union Lucca recreated by Crosthwaite & Gardiner based on historical photos and various other documents from the archives. 

This British restoration and recreation specialist company is no stranger to Audi pre-War products, having completed several Silver Arrows cars and the Typ 52 for the company.

C&W took three years on the Lucca car project, completing it in early 2026. All components were handcrafted especially for this model: most significantly its streamlined bodywork, on which the cockpit canopy and the tapered tail were particularly labour-intensive. 

Project manager for the construction of the Auto Union Lucca was Timo Witt. He had been in charge of the historic vehicle collection at Audi Tradition since 2015 and previously spent more than 10 years as a motorsport engineer. 

Timo Witt shared 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 the car’s durability and maximising efficiency in the project’s implementation were also important to us”. 

For example, Audi Tradition fitted the Lucca with the 16-cylinder engine from the Auto Union Type C, because its six-litre engine was visually indistinguishable from the five-litre engine and C&W had already produced several of the larger-capacity engines. That meant that all recreated pre-War Auto Union cars used the same remanufactured engine.

The Auto Union Lucca also features several modifications that were implemented for the Avus race in Berlin in May 1935, such as the ventilation system. 

Timo Witt: “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 and the body panels, the Auto Union Lucca can be converted into the second Avus car. 

After being unveiled in Lucca, Italy, the Rennlimousine was scheduled to make its first public, powered appearance at the Festival of Speed from 9th to 12th July, 2026, at Goodwood.

Technical data 

Auto Union Lucca 2026 model 

Engine: 16-cylinder engine with compressor, 6005cc (as in the Auto Union Type C from 1936)

Power output” 520PS (382kW) at 4500rpm

Maximum speed: Not specified

Fuel: 50% methanol; 40% premium unleaded and 10% toluene 

Dimensions (L/H/W) Wheelbase: 4570 / 1200 / 1700mm; 2800mm

Kerb weight: 960kg

Exterior colour: Cellulose silver 

Total production run: One-off

• BACK TO RESTORATION PROJECTS