The stillborn 1.5-litre car: why it (almost) did exist
- Jeroen Bruintjes
- October 8, 2002
- 1938 Donington GP - Tazio's winning ways in Britain, by Arjan de Roos
- The 1939 season - The 1939 Championship mystery, by Leif Snellman/Don Capps
- Tazio Nuvolari - Mantua's Great Little Man, by Leif Snellman
- The early Auto-Unions - From P-Wagen to A-type, by Leif Snellman
- Auto Union - The history of the AU racing department, a triptych of essays on the Saxonian marque's racing exploits, by Holger Merten
- Part 1: The small workshop that created motor racing history (1931-1935)
- Part 2: The comeback years (1936-1939)
- Part 3: The scars of war (1939 and beyond)
- Sokol 650 - Post-war Auto Union in disguise or a socialist F2 effort? Secrets of Tom Wheatcroft's "Type E" unveiled, by Jeroen Bruintjes/Holger Merten
Tazio Nuvolari, Hermann-Paul Müller, Rudolf Hasse, Hans Stuck, Ulli Bigalke, Georg Meier
Auto Union 1,5 Liter or Typ E
Where and when?
Never raced – never built?
Being one of the two great pre-war constructors, the small Auto Union Rennwagen-Abteilung struggled to remain afloat when motorsport changed to 1.5 litre. After a dramatic set-back caused by a hesitating board of directors and a pro-Mercedes government, 1940 saw remarkable progress, despite a war-spoilt supply chain and personnel shortage. It may have led to one of the most advanced designs of its day, one that was far nearer completion than has always been assumed.
Ever since the 1930s, Auto Union racecars and their drivers have been the subject of legends. War stories fed on Rosemeyer’s death or Nuvolari’s successes in the Typ D. No wonder with some of the world’s greatest drivers steering hundreds of supercharged horsepowers to speeds over 400 kph.Yet although the outbreak of WW2 meant an abrupt halt to racing, no such thing happened to the stories. They culminated after the war into decades of speculation on what happened to the cars after the Soviet occupancy of the Chemnitz factories while the West had been left with almost nothing. The discovery of some information and four cars changed this, with two Ds coming from the Ukraine, one D emerging in Prague and a Typ C/D hillclimber from Riga. So where’s the Typ E?
It has never been a secret that Auto Union thought about a successor to the 3-litre, V12 Typ D. The new car was assumed to suit the 1.5-litre Grand Prix formula – hitherto the voiturette formula – that was proposed for the early 1940s. Arch rival Mercedes-Benz had already secured victory in this formula by racing its hastily developed W165 at the 1939 Tripoli GP. And although an equivalent Auto Union never raced, few believed the “official” view that Auto Union had mostly sat on its back and let their opponents take the lead, leaving the Typ E to the intriguing domain of what-ifs. A view that is more or less based on Auto Union’s chief designer Richard Eberan von Eberhorst, who in 1982 was quoted saying that a 1.5-litre car was never built. “Some parts and a single-cylinder test engine, yes. But a complete car, no.”
For years, Eberan’s statements were all there was to know about the Typ E project. Until recently when a small article emerged from British archives. In its October 3rd 1945 issue, The Motor magazine had given an intriguing twist to the story by interviewing Sir Roy Fedden, who had travelled to Germany as a special technical advisor to the Minister of Aircraft Production. Fedden had met with Richard Bruhn, former Auto Union director, who was in allied custody at the time. As Bruhn told Sir Roy, “They had completed construction of a team of 1.5 litre racing cars and claimed that in tests they had given very good results. The cars were stored in a garage in a suburb of Chemnitz and, according to Bruhn, they lay for a long time in the no man's land between the advancing American/British and Russian forces. He said that up to the middle of June they could have been taken away by any British representatives who were interested, but the Red Army took control only a few days before Sir Roy arrived in Germany, and since then nothing has been heard of the cars.”
One might agree that this is merely hearsay versus solid history. However, Auto Union’s racing history is far from solidly documented. Around 1941 it became standard practice to recycle old documents, since paper was so scarce. Then Soviet forces took control of the factory and sent quite a bit of the archives to Russia in 1945. What was left remained almost untouched and uncatalogued for decades. These documents are now stored in the Saxonian State Archives in Chemnitz as Bestand der Auto Union AG. They show lots of gaps, but a new, impeccable index was completed in 2001. Here, it becomes clear just how inconclusive the written history of the Typ E project is. Also, it shows strange contradictions to Eberan’s 1982 memorandum, which more or less denies his 1940 memos. So let’s take a chronological view, going back to where it all started: a corporate letter.
The new formula
On November 12th 1938, Auto Union’s Rennwagen-Abteilung (racing department) sent its planning for 1939 to corporate director Bruhn. They attached a note to it, giving expression to the growing concerns about the proposed 1.5-litre formula. Bruhn was urged to arrange a board meeting on the subject, since it seemed that in the near future, this formula would dominate international racing. The Abteilung feared that 1.5-litre racing would be a succesful foreign attempt to bring an end to German domination in motorsport. On top of that, rumour had it that Mercedes-Benz already had a 1.5-litre car underway. However, nothing happened. So five months later, on April 12th 1939, another memo landed on the board secretary’s desk. Formal, yet annoyed in tone, it insisted that Auto Union do something to gain a dominating position in the upcoming 1.5-litre races. After all, weren’t these formula changes already known since last spring? And hadn’t Mercedes-Benz immediately jumped on the new bandwagon, secretly developing a new car? While Auto Union had done nothing, the guys in Stuttgart-Untertürkheim would race in the upcoming Tripoli GP, on May 7th! The letter asked for a decision: either devote all resources to a new 1.5-litre project or wait and see how things develop, leaving Auto Union trailing behind and losing face all over the world.
At the same time, the Rennwagen-Abteilung in Zwickau and the R&D department in Chemnitz had taken action for themselves. A few weeks before, on March 15th 1939, they’d already sat down with some of the assistants to the board of directors. During this meeting, sketches of a new car quickly emerged, as is shown in a memo dated March 20th:
Prelimary technical specifications
Engine: 1.5 litre
Cylinders: 12, 125 cc each, meaning 56 stroke and 53 mm bore
Power output: 260 bhp
Wheelbase: 2500 mm
Camshaft, tappets and valve springs would be of a totally different kind than those in previous engines. Also, the designers proposed a new, double “concentric” compressor instead of the familiar Roots supercharger, 14 mm Bosch plugs and a gearbox configuration that would enable the rear axle to move more freely. The designers were in a hurry: a first car should be ready by 1940. Engine drawings were expected to be completed only two months after the meeting, so that a necessary single-cylinder prototype could be built in the summer of 1939.
However, the understaffed Rennwagen-Abteilung could spare no time from the efforts needed to complete the ongoing 1939 GP season. New developments had to wait and again all stayed quiet for a while. Until November 20th 1939, when Auto Union’s chief designer Eberan met in Berlin with Neubauer (Mercedes Benz), Holzheuer (Continental Tyres) and some Nazi chiefs, including Adolf Hühnlein from the governmental department for motor racing. Not only were they to bring an end to the 1939 European Championship debate, the agenda also saw some decisions to be made on the upcoming formula changes. Hühnlein kicked off with an urge to keep all efforts going, in spite of the war. He pointed out that several Italian races were planned, some of them to the 1.5-litre formula, and professional motor racing might soon be taken up again in countries like Finland, Sweden, Yugoslavia, Hungaria, Greece or Russia. Therefore he deemed it necessary for Mercedes-Benz and Auto Union to keep the existing 3-litres in running order and develop 1.5-litres for future races at the same time. However, when it came to extra financial support, nothing should be expected, though Hühnlein did promise to free drivers and technicians from army duty and find a solution to the growing supply problems.
Neubauer, Eberan and Holzheuer were sceptical. The Mercedes-Benzes were now thought to be mere studies, definitely no 1940s racing material. As to the Auto Union project: it had ground to a halt because of shortage in materials and suppliers. Keeping the 3-litres running had already been quite a hassle. Also, tires for existing cars were becoming a rarity and fabricating new ones would be very difficult due to rubber shortage. And then there was the racing program itself: apart from a German GP on the new Großdeutschlandring (near Dresden) they could only participate in the Italian programme, which wasn’t even known. Hühnlein, sensing that the three factories were in remarkable agreement, gave in and promised to arrange something with the Italians. On January 8th and 9th 1940, the team met again in Merano, this time with Italy’s Furmanik, Filippini, Costantini and Ricart (Alfa Romeo) and Germany’s Seiler (Mercedes-Benz) and Eberan. After two days of intense debating the Germans had gained nothing. Almost all racing in Italy would be 1.5-litre, simply because Alfa Romeo said they were unable to develop a 3-litre. Leaving only the German GP on the Großdeutschlandring and either the Coppa Ciano at Leghorn or the Coppa Acerbo at Pescara to the 3-litre domain. The two German factories were allowed to decide which of these Italian races they preferred, a small and patronising gesture from the Italians.
Shortage of materials...
For Auto Union, the scene was set and on March 29th 1940, the Rennwagen-Abteilung wrote again to the board. They briefly mentioned the near-to-readiness of the 3-litre Typ Ds and went on about the Typ E. Director Werner had taken charge of the developments and engine models were already done. Also, they had agreed on the front axle and chassis construction, with parts being made as-they-wrote. About 60 percent of all materials could be taken from existing Typ D supplies. Completion of the gearbox, rear axle, brakes and steering was at hand, noting that the needed light-metal parts were very hard to come by. The constructors already used up all personal favours for these. As for fuel: the day before, a representative of fuel supplier Rhenania Ossag had visited the plant and had promised 3000 litres. Tyres for the 1.5 litre were a problem, however: remaining Auto Union stocks only fitted the Typ Ds.
Director Bruhn sent a copy of this letter on to NSKK leader Hühnlein and, strangely enough, Mercedes-Benz. Hühnleins response is a true example of a military-style scolding. On April 16th 1940, he wrote to Bruhn:
“As I was very pleased about your initial efforts to deliver the racecars, it amazes me even more to see how you can now whine about such villainous few kilos of metal. I love my job, yet I wish that large companies like yours would not bother me with these official nullities. By the way, Daimler-Benz has already invited me to witness the testing of their new racecar. Seems like Untertürkheim has overcome these so-called problems.”
... and men
Auto Union picked up a frantic pace and pursued both the D and E projects simultaneously, as is shown in Eberan’s detailed progress report of May 22th 1940. Three revised Typ Ds were thought to be ready by July, in time for the Coppa Acerbo at Pescara on August 18th. The 3-litres had been thoroughly redesigned, with more power, a better carburettor and a fully synchronised gearbox. All that was needed were some gear wheels, rods and a rear axle. As for the Typ E: one was planned to be ready by the end of 1940. Many parts were already being made and Eberan mentioned several fixed delivery dates for gearbox, brakes, bodywork, carburettor, supercharger and engine parts. At the same time, he noted how difficult it became to monitor these dates, to keep in close touch with the suppliers and to find all available production facilities. The war already slowed things down and Eberan insisted on the appointment of personnel dedicated specifically for this labour-intensive job.
His wishes remained unanswered. On October 11th, the Rennwagen-Abteilung complained to the board that Mercedes-Benz was leading “by having a proven, reliable car on the streets while we haven’t even decided what our car is going to look like”. November 16th: again a memo to the board, stating that there were now only 6 men left to pursue the project. Strangely enough, money was no object anymore. The memo estimated the costs of building three 1.5-litre engines and two complete Typ Es to 295,000 Reichsmarks. Since the Nazi government granted Auto Union 300,000 Reichsmarks each year, also in 1940 and 1941 (the last payment took place on February 15th 1941) ample financial room should have existed for at least one completed car. To reach this small goal, all efforts were now focused on the Typ E. In the last months of 1940, the Zwickau developers completed several subprojects, including supercharger tests, which in the end gave satisfactory results. Also, a waterpump was being tested and found OK in December 1940. Then, on the last day of 1940, the Rennwagen-Abteilung sent a complete 1940 progress report to the board.
Versuchsbericht 307, signed by Eberan and dated December 30th 1940, claims that all 3-litre developments had been cancelled in favour of the 1.5-litre. It goes on at length about the Typ E developments. There had been numerous tests of two and four valve per cylinder configurations. The 4V-models showed better results, but parts shortage prohibited more tests. A 125 cc single-cylinder test engine had been run with great results at up to 7000 rpm with a power output of more than 200 hp/litre, and much more was within reach. Camshaft and valve springs, engine blocks and heads were ready and had done 11400 rpms without any problems.
Further on, they had developed and tested hydraulic valve tappets that eliminated the need for adjusting valve clearance and were better suited for high rpms. Also, engineers had solved the problems of wear and excessive friction with the concentric compressor. Solex had failed to deliver the new carburettor, but Auto Union’s own fuel-injection alternative was up and running on a 3-litre engine, with great results, although the response to accelerator movements was still a little sluggish. For this, an extra pump was already being made. Further on, the compressor test results appeared acceptable enough with existing carburettors.
Report 307 specifically states that delivery of the crankshaft was the factor that determined completion of the first 1.5-litre engine. As for the rear axle: a tube-supported configuration was tested and completed. The chassis was ready, although found to be not as stiff as the one on the Typ D. The Abteilung had toyed with the idea of using two gyroscopes to counter the notorious tail wag of rear-engined cars. Using a model with air-driven gyroscopes, they had achieved surprising results and exceptional stability.
This report is perhaps the most important one, since it shows Eberan countering his own 1982 statement. Unfortunately, the progress reports come to an abrupt end here. Which is surprising, given the thorough paper trail of the Rennwagen-Abteilung. Also, other documents indirectly show development going on far beyond 1940. Supercharger improvements went on until May 15th 1941, for example. And the Abteilung sent detailed cost reports to the board every couple of months, the last one of which is sent in the spring of 1942. It shows how money was spent on engine development, chassis and drivetrain construction plus tools and workshop machinery, with amounts decreasing every month.
So where is it?
It seems unlikely that two cars could have been made during the following years, as Bruhn stated. Building one car was already quite a burden. Also, work must have come to a standstill later in the war, with almost all people being drafted in 1943 and bombing runs starting in 1944. It is impossible to conclude whether the Auto Union Typ E did or did not exist. But let’s try to see where it ended.
- On December 30th 1940, the Hirth factory had not delivered the crankshaft yet, but had been working on it for some time. One should note that Hirth already had a reputation for not delivering on time and on spec: there had been numerous problems with the Typ D crankshafts in 1938 too. Whether or not they ever delivered for the Typ E remains speculation.
- According to the reports mentioned above, crankshaft, brakes, wheels and tyres were all that was missing and keeping Auto Union from completing a driveable prototype (without bodywork).
- The sudden halt in reports after December 1940 appears to be more of an archive gap than a true halt in progress, which is confirmed by the ongoing costs reports.
- Eberan left Auto Union somewhere early 1941 and did not witness the end of the project. Mechanic Ludwig Sebastian was one of the last to be in the Rennwagen-Abteilung and claimed that an estimated 20 cars and lots of parts were stored in various locations around Zwickau to avoid being robbed or bombed.
- Zwickau is about 40 km from Chemnitz and the area between both cities sees lots of disused mines. West and south of Chemnitz was no-man’s land between the Russian and American forces after the fights ceased early May 1945. The Red Army took control of this area in July. This part of Bruhn’s statements is plausible.
- Bruhn left Chemnitz on May 7th, 1945, a day before Chemnitz itself was occupied by the Red Army. He was afterwards taken in Allied custody until 1947.
- Bruhn may have felt like the unterdog, compared to rival Mercedes-Benz with their succesful 1.5-litre project. Hühnlein’s scolding and his own failure to recognize the need for a Typ E in 1938/39, when there was still ample time, might have led him to overdo his statements to Fedden.
It appears that the Rennwagen-Abteilung was very near to completing a prototype and might even have produced something that drove in the following years. However, documents, engine parts, axles and chassis have simply vanished. Since it was the most advanced project, it is likely that they were hidden in a disused mine like all other racecars.
Perhaps the mortal remains today still lie in a Russian shed?
Auto Union 1,5 Liter or Typ E
- Type: 12-cylinder, 60-degree V
- Size: 1481,8 cc
- Stroke x bore: 53 x 56 mm
- Compression: 10:1
- Power: 260 bhp (327 bhp when using the 220.7 bhp/litre test results from the 1-cylinder testbed)
- Valves: 2 per cylinder, 3 overhead camshafts, hydraulic tappets
- Fuel system: 2 concentric compressors, 1.9 bar boost pressure, Solex carburettors or in-house developed fuel injection
- Gearbox: 6-gear, synchronised
- Wheelspan: 2500 mm
- Bestand der Auto Union AG, Sächsisches Staatsarchiv Chemnitz
- Adriano Cimarosti: The Complete History of Grand Prix Motor Racing, 2nd English edition, Aurum Press, London 1997
- Martin Kukowski: Findbuch zu den Beständen der Auto Union AG, Mitteldeutscher Verlag, Halle-Saale 2000
- Stefan Knittel: Auto Union Grand Prix Wagen, Schrader & Partner, München 1980
- Peter Kirchberg: Grand-Prix-Report Auto Union 1934-1939, VEB Verlag für Verkehrswesen, Berlin 1982
- Peter Vann: Neusilber, Motorbuch Verlag, Stuttgart 2001
- AtlasF1 Nostalgia Forum, Richard Armstrong and Holger Merten