For other uses, see. download free New Holland Tz24 Service Manual. VTEC (Variable Valve Timing & Lift Electronic Control) is a system developed by which was said to improve the volumetric efficiency of a, resulting in higher performance at high RPM, and lower fuel consumption at low RPM. The VTEC system uses two (or occasionally ) profiles and hydraulically selects between profiles. It was invented by Honda engineer Ikuo Kajitani. Challenge Xtreme Trimmer Manual download free. It is distinctly different from standard VVT () systems which change only the valve timings and do not change the camshaft profile or valve lift in any way. download Prado Maintenance Manual torrent more. Contents • • • • • • • • • • • • • • • • Context and description [ ] levies a, and Japanese auto manufacturers have correspondingly focused their efforts toward improving the performance of their smaller engine designs through means other than displacement increases.