Spiess Tuning is the common identity of Siegfried Spiess Motorenbau GmbH, a motor vehicle engine tuning company based in Ditzingen

Ditzingen

Ditzingen is a town in the district of Ludwigsburg, Baden-Württemberg, Germany. It is situated about 10 km northwest of Stuttgart, and 12 km southwest of Ludwigsburg. The Hirschlanden transmitter is located near Ditzingen-Hirschlanden...

, Baden-Württemberg

Baden-Württemberg

Baden-Württemberg is one of the 16 states of Germany. Baden-Württemberg is in the southwestern part of the country to the east of the Upper Rhine, and is the third largest in both area and population of Germany's sixteen states, with an area of and 10.7 million inhabitants...

, Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

. Today Spiess Tuning is most famous for its Formula 3 motor racing engines based on the Opel Family II

GM Family II engine

The Family II is a straight-4 piston engine that was originally developed by Opel in the early 1970s. It was used in the Opel Ascona and Opel Kadett and their corresponding sister models the Vauxhall Cavalier and Vauxhall Astra...

 and two iterations of Volkswagen R4 engines.

In addition, Spiess has worked on many different engines with motor racing applications, including a 4.0 litre V8 for use in the DTM

Deutsche Tourenwagen Masters

The Deutsche Tourenwagen Masters is a touring car racing series based in Germany, but also with rounds elsewhere in Europe....

 Opel Vectra

Opel Vectra

The Opel Vectra is a large family car that was engineered and produced by Opel. In the United Kingdom, the car was sold under the Vauxhall marque as the Vauxhall Cavalier and later as the Vauxhall Vectra, from 1995 onwards...

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