Editing Auto Union (section)

==The Auto Union racing cars==
{{Main|Auto Union racing car}}

===Background===
Auto Union chairman, [[Klaus von Oertzen|Klaus, Baron von Oertzen]], wanted a showpiece project to announce the new brand. At the 1933 Berlin Motor Show, [[German Chancellor]] [[Adolf Hitler]] announced two new programs:<ref name="David">{{cite web|url=http://www.ddavid.com/formula1/auto_c.htm|title=Auto Union Type C|publisher=DDavid.com|access-date=2009-06-20|archive-date=10 October 2012|archive-url=https://web.archive.org/web/20121010180201/http://www.ddavid.com/formula1/auto_c.htm|url-status=dead}}</ref>
*The people's car (''Volks wagen''): a project that became the [[Volkswagen Beetle|''KdF'' car]] – the "Strength through Joy" car 
*A state-sponsored motor racing programme: to develop a "high speed German automotive industry," the foundation of which would be an annual sum of {{Reichsmark|500,000|link=yes}}

At fellow director's [[Adolf Rosenberger]] insistence, von Oertzen met with Dr. [[Ferdinand Porsche]], who had done work for him before, and developed his own [[P-Wagen project]] racing car based on the new {{convert|750|kg|lb|abbr=on}} formula.<ref name="David"/>

German racing driver [[Hans Stuck|Hans Stuck Sr.]] had met Hitler before he became Chancellor, and not being able to gain a seat at Mercedes, accepted the invitation of Rosenberger to join him, von Oertzen, and Porsche in approaching the Chancellor. In a meeting in the [[Reich Chancellory]], Hitler agreed with Porsche that for the glory of Germany, it would be better for two companies to develop the project, resulting in Hitler agreeing to pay [[Pound sterling|£]]40,000 for the country's best racing car of 1934, as well as an annual stipend of {{Reichsmark|250,000}}<ref name="David"/> (£20,000)<ref>Setright, L. J. K. "Mercedes-Benz: The German Fountain-head", in Northey, Tom, ed. ''World of Automobiles'' (London: Orbis, 1974), Vol. 11, p.1311.</ref> each for Mercedes and Auto Union. (In time, this would climb to £250,000.)<ref name="Setright, p.1312">Setright, p.1312.</ref> This highly annoyed Mercedes, who had already developed their [[Mercedes-Benz W25]]; nevertheless, Mercedes was gratified, its racing program having financial difficulties since 1931.<ref name="Setright, p.1312"/> It resulted in a heated exchange both on and off the racing track between the two companies until World War&nbsp;II.

Having garnered state funds, Auto Union bought Porsche's ''Hochleistungsfahrzeugbau GmbH (HFB)'' (High Performance Car Ltd.) and hence the P-Wagen Project for {{Reichsmark|75,000}}, relocating the company to Auto Union's [[Horch]] plant at [[Zwickau]].<ref name="David"/>

===Design===

The Auto Union racing cars types A to D were built as [[Grand Prix motor racing|''Grand Prix'']] [[racing car]]s from 1934 to 1939. They resembled the earlier Benz [[Mercedes-Benz in motorsport#The Silver Arrows (1923–1931, 1934–1939)|''Tropfenwagen'']], also built in part by Rumpler engineers,<ref>Wise, David Burgess. "Rumpler: One Aeroplane which Never Flew", in Northey, Tom, ed. ''World of Automobiles'' (London: Orbis, 1974), Vol. 17, p.1964.</ref> The only ''Grand Prix'' racers to wear Auto Union's four-ringed logo, they were particularly dominant in 1936. From 1935 to 1937, Auto Union cars car won 25 races, driven by [[Ernst von Delius]], [[Bernd Rosemeyer]], [[Hans Stuck|Hans Stuck Sr.]], and [[Achille Varzi]]. Much has been written about the difficult handling characteristics of this car, but its tremendous power and acceleration were undeniable – a driver could induce wheelspin at over {{convert|100|mph|km/h|abbr=on}}.

The cars used [[supercharger|supercharged]] [[piston engine]]s; eventually producing almost {{convert|550|hp|kW PS|lk=in|abbr=on}}, designed to provide optimum [[torque]] at low engine speeds. Rosemeyer would later drive one around the [[Nürburgring]] in a single gear, to prove the engine was flexible enough to do it. Unlike its rivals, it had a [[rear mid-engine, rear-wheel-drive layout]]. The [[fuel tank]] was located in the centre of the car, directly behind the driver (who would be placed well towards the front), so the car's front-rear weight distribution would remain unchanged as fuel was used – exactly the same location used in modern open-wheel racing cars, and for the same reason. The chassis tubes were initially used as water carriers from the radiator to the engine, but this was eventually abandoned after they often sprung small leaks.

===Racing results===
{{Main|Auto Union racing car}}
The list of drivers for the initial 1934 season was headed by Stuck; he won the [[German Grand Prix|German]], [[Swiss Grand Prix|Swiss]], and [[Czechoslovakian Grand Prix|Czechoslovakian]] events, along with wins in a number of [[Hillclimbing|hill climb]]s, becoming European Mountain Champion.

In 1935, the engine had been enlarged to {{convert|5|L|cuin|0|abbr=on}} displacement, producing {{convert|370|bhp|kW PS|0|abbr=on}}. [[Achille Varzi]] joined the team and won the [[Tunis Grand Prix]] and the [[Coppa Acerbo]]. Stuck won the Italian Grand Prix, plus his usual collection of hill-climb wins, again taking the European Mountain Championship. The new sensation, Rosemeyer, won the Czech Grand Prix.
[[File:Streamlined Auto Union.jpg|thumb|left|Hans Stuck Sr. in an aerodynamic Type B in Italy]]

Stuck also managed to break speed records, reaching {{convert|199|mph|km/h|0|abbr=on}} on an Italian ''autostrada'' in a closed-cockpit streamliner.<ref name="Eyston">{{cite book|title=Motor Racing and Record Breaking|author=G.E.T. Eyston|author2=Barré Lyndon|year=1935|author-link=George Eyston|author2-link=Barré Lyndon}}</ref> Lessons learned from this streamlining were later applied to the [[Mercedes-Benz T80|T80]] [[land speed record]] car.
[[File:Auto-union-type-d.jpg|thumb|1939 Type C/D V16 hillclimb car]]

For 1936, the engine had grown to a full {{convert|6|L|cuin|0|abbr=on}}, and was now producing {{convert|520|bhp|kW PS|0|abbr=on}}; in the hands of Rosemeyer and his teammates, the Auto Union Type C dominated the racing world. Rosemeyer won the [[Eifelrennen]], German, Swiss, and Italian Grands Prix, as well as the ''Coppa Acerbo''. He was crowned [[European Champion (auto racing)|European Champion]] (Auto Union's only win of the driver's championship), and also took the European Mountain Championship.  Varzi won the Tripoli Grand Prix, while Stuck placed second in the Tripoli and German Grands Prix, and [[Ernst von Delius]] took second in the ''Coppa Acerbo''.

In 1937, the car was basically unchanged and did surprisingly well against the new [[Mercedes-Benz W125]], winning five races to the seven of Mercedes-Benz. Rosemeyer took the Eifel and [[Donington Grand Prix|Donington]] Grands Prix, the Coppa Acerbo, and the [[Vanderbilt Cup]]. [[Rudolf Hasse]] won the [[Belgian Grand Prix]].

In addition to the new {{convert|3|L|cuin|0|abbr=on}} formula, 1938 brought other challenges, principally the death of Rosemeyer early in the year, in an attempt on the land speed record on a German ''autobahn''. [[Tazio Nuvolari]] joined the team, and won the Italian and Donington Grands Prix, in what was otherwise a thin year for the team, other than yet another European Mountain Championship for Stuck.

In 1939, as war clouds gathered over Europe, Nuvolari won the [[1939 Belgrade City Race|Yugoslavia Grand Prix]] in Belgrade, while [[Hermann Paul Müller|Hermann P. Müller]] won the [[1939 French Grand Prix]].

{{Silver Arrows}}