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Advantage of Lightweight Valve Train Component on Engines
ISSN: 0148-7191, e-ISSN: 2688-3627
Published February 23, 1998 by SAE International in United States
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Recently, customer requirements for engines have become more demanding, not only in terms of power, but also for fuel economy. To deal with these demands, the four-valve per-cylinder engine is now widely used for passenger cars. The direct acting systems and roller rocker arm system are two major valve train systems for passenger car engines. The advantage of a direct-acting system is its simple mechanism and low cost. However, it has higher friction than a roller rocker arm system.
To improve on this situation, we at FujiOozx have worked on reducing the moving mass for the direct acting system. Using newly-developed lightweight valve train components, moving mass was reduced by 28%. Consequently, approximately 40% of friction loss was eliminated and improvement of noise and smaller engine package size were achieved (with optimization of cam profile and valve spring) to create a lightweight, direct-acting valve system.
CitationKanzaki, T., Hara, N., Mori, A., and Ohtsubo, K., "Advantage of Lightweight Valve Train Component on Engines," SAE Technical Paper 980573, 1998, https://doi.org/10.4271/980573.
- Izumita et al. “A Study of the Effects of Ceramics Valve Train Parts on Reduction of Engine Friction,” JSAE Proceedings on Spring Convention 935 1995 197
- Katoh et al. “An Analysis of Friction Reduction Technique for the Direct-Acting Valve Train System of a New-Generation Lightweight 3-Liter V6 Nissan Engine,” SAE 940992