VTEC
VTEC
VTEC is a valvetrain system developed by Honda to improve the volumetric efficiency of a four-stroke internal combustion engine. The VTEC system uses two camshaft profiles and hydraulically selects between profiles. It was invented by Honda engineer Ikuo Kajitani, and was the first system of its kind. It is distinctly different from standard VVT which advances the valve timing only and does not change the camshaft profile or valve lift in any way. Different types of variable valve timing and lift control systems have also been produced by other manufacturers VVTL-i from Toyota, VarioCam from Porsche, NeoVVL from Nissan, etc.The above text is a snippet from Wikipedia: VTEC
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