Spiess Tuning

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Spiess Tuning is the common identity of Siegfried Spiess Motorenbau GmbH, a motor vehicle engine company based in Ditzingen, Baden-Württemberg, Germany.

Siegfried Spiess Motorenbau GmbH is a family-run company that develops, manufactures and services its own high-performance engines in second generation. Currently, three pillars form the Siegfried Spiess Motorenbau GmbH: Spiess RACing, Spiess Classic and Spiess CNC. Spiess RACing is responsible for the development, production and assembly of racing engines. This also includes the on-site support of the teams and drivers. Spiess Classic is mainly concerned with the design and restoration of young and classic car engines. Spiess CNC manufactures complex one-offs and also offers contract manufacturing, both for private individuals and for companies.