In order to develop its next generation of engines for the mainstream market, Honda's NCE (New Concept Engine) program was launched in March 1984. Specific targets identified through the program included high torque in both the low- and high-rpm ranges and dramatic increases in horsepower per liter. The program was a success, resulting in a series that included the DOHC engine found in the 1985 Civic and Integra, and the SOHC center-plug engine in the 1987 City.
Ikuo Kajitani, who was employed in the First Design Dept at Honda's Tochigi R&D Center, was involved in the development of these four-valve engines. Through his experience in engine design, Kajitani had become convinced that Honda's next engine should offer a mechanism that could alter the timing of the valves.
"Characteristically," Kajitani said, "four-valve engines are known as high-revving, high-output machines. And for that reason we knew it would be quite difficult to achieve low-end performance if the engine's displacement were too small."