Interview with a Powertrain Engineer: Additional Value of VC-T Engine Breaks into Brand-new Field of Mass-manufactured Engine

In the fall of 2016, Nissan Motor announced the world's first mass-production variable compression ratio (VCR) engine the VC-Turbo (or VC-T) engine. The merit of changing the compression ratio is well-known, but the VC-T engine has an additional value as well which is not well recognized. In this regard, FOURIN spoke with Dr. Shunichi Aoyama, the creator of the VC-T engine, in detail. According to Dr. Aoyama, the reason why the VC-T engine can be mass-produced is exactly because of these additional values. Many VCR concepts developed before, but they had many problems such as cost, complex structure and low reliability which prevented their mass manufacturing. In light of this situation, since the start Nissan Motor’s VC-T development team believed that the key to mass production is to offer added value (product appeal improvement) apart from VCR. As a result, in addition to overcoming the problems of conventional engines, it opened new possibilities for future engine advancement. Most of the additional value of the VC-T engine is obtained by making the stroke characteristics of the piston close to sine curve motion.

---