Siegried Spiess turns his hobby into a profession with NSU. However, his own successes as a racer are not to remain the only ones. In the small garage in Stuttgart-Weilimdorf, he starts tuning vehicles for other racers. Due to the high demand for his products and services, the NSU business quickly turns from a sideline into a full-time job for Siegfried Spiess.

After his first two personal racing successes on NSU, the Neckarsulm-based company also becomes aware of him and he officially becomes an NSU works team driver. Here, it is important to mention that Siegfried Spiess is not only responsible for the engine, but also for the preparation and setup of the entire vehicle.

In order to meet the high demand of his customers, "Siggi" Spiess has to retire from active racing in 1969.

After NSU merges with Audi in 1969, Siegfried Spiess also makes the change. After the last NSU vehicle rolles off the production line in 1972 and Willi Bergmeister wins the last championship title with a Spiess-NSU engine in 1974, Siegfried Spiess reorients himself aswell and for the first time focuses on the 1.6 liter GTI power unit from the Golf/Scirocco series, thus opening up a new opportunity for Spiess Tuning to get involved in another racing series. And this lays the foundation for Formula 3. More about it in the next article!