Stefan Zima studied mechanical engineering at the Technical University of Berlin (majoring in engines and machines). He came into contact with high-speed, heavy-duty engines for special applications when, after obtaining his intermediate diploma with Deutsche Bundesbahn [German Federal Railways], he underwent training to become an engine driver on diesel locomotives of the V 60, V 1002, V 160, and V 2001 series. After his examination in humanistic, in 1967 he gained his full diploma with a thesis on experimental investigations into a heat-transfer problem. Subsequently, Zima worked as assistant engineer on merchant-navy ships, where he acquired a thorough knowledge of the operation, maintenance, and repair of marine propulsion systems, including those powered by high-speed engines. From 1968 to 1977, DiplIng. Stefan Zima worked in the R&D division of Maybach-Mercedes-Benz Motorenbau (now: MTU Friedrichshafen GmbH), and was last employed as deputy head of a design department. In 1977 he joined the Giessen-Friedberg University for Applied Sciences as a lecturer in piston engines and head of the IC laboratory. He was appointed professor in 1979. Also during his service as a university lecturer, Zima maintained contact with the everyday world of engine technology in a variety of ways, e.g., by trips on motor ships or by driver training and testing on tracked vehicles (Leopard 1 A 4 combat tank). In 1985 he was awarded his doctorate in engineering from the Technical University of Berlin with a thesis on "The Development of High-Speed Heavy-Duty Engines in Friedrichshafen" (VDI-Verlag, Dusseldorf, 1987). He published a number of books on internal combustion engines, e. g., Hochleistungsmotoren. Karl Maybach und sein Werk, [Heavy-Duty Engines. Karl Maybach and His Work], VDI-Verlag, Dusseldorf, 1992 and 1995 (co-author); Kurbeltriebe, [Development of the Crank Assembly], Vieweg-Verlag, Wiesbaden, 1999; and Ungewoehnliche Motorkonstruktionen [Unusual Engine Designs], Vogel-Verlag, Wurzburg, 2003. Dr. Zima unexpectedly passed away in April 2004.
After graduation from high school, Ernst Greuter completed training as a motor vehicle mechanic. After passing his journeyman and master's exams, he attended engineering school. In 1950, he joined his father's business, "Motoren-Greuter," an engine overhaul shop located in Saarbrucken, Germany. In that same year, he set up a small subsidiary in Algiers, Algeria, specialising in cylinder boring and crankshaft grinding, with a small sales office. In 1951 he established additional engine overhaul branches in Idar-Oberstein and Mainz, Germany. In 1952 and 1953, Greuter served as an engineer trainee with several vehicle and engine component manufacturers in Germany and abroad. In 1955, he was given overall technical responsibility for all of the family firm's engine overhaul facilities. Also beginning in 1955, Greuter worked as a combustion engines consultant (gasoline and diesel). He participated in research, development, and material testing activities with various engine component manufacturers in Germany and abroad. Greuter conducted tests of new designs and materials on diesel and gasoline engine test stands. In 1964, he established additional subsidiaries in Central and South America, and began license manufacture of ocean-going diesel engines and manufacture of exchange engines. In addition to his work as technical director and managing director of "Motoren-Greuter" GmbH, beginning in 1975 Greuter operated an engineering and consulting office which specialised in planning and establishing engine repair facilities, exchange engine manufacturing, and production of engine components in Germany and overseas. Additional specialities included personnel training, and combustion engine seminars for the motor vehicle repair trade and for engine specialists. Periodically Greuter served as a visiting instructor at various educational facilities overseas. From 1987 to 1997, he had an independent consulting service, specialising in combustion engines, engine overhaul, and the outfitting of engine and motor vehicle repair facilities.