valve duration

valve duration

valve durationclick for a larger image
The length of time, measured in degrees of crankshaft rotation, an intake or exhaust valve in a reciprocating engine is open.
References in periodicals archive ?
The South Korean company Hyundai has developed, allegedly, the world's first system of continuous change in the duration of valve opening, called Continuously Variable Valve Duration. CVVD technology is a further evolution of various variable valve timing systems that can be found in any modern car today.
Hyundai Motor Group said it has developed the world's first continuously variable valve duration (CVVD) technology to feature in its future models.
The Continuously Variable Valve Duration system is capable of adjusting the duration of valve opening and closing cycles.
Hyundai Motor Group has developed the world's first Continuously Variable Valve Duration (CVVD) technology to feature in future Hyundai vehicles.
Previous variable valve control technologies could not regulate valve duration, as the valve's closing timing was subordinate to opening timing and could not respond to diverse driving situations.
The Type R has a 2.0-litre 197bhp i-VTEC engine with a seven-speed gearbox, that's six close-ratio forward gears, all pulling well within the VTEC rev range of 6,0008,000, where the valve duration changes and the fun really begins.
Hyundai Motor Group has developed the worlds first Continuously Variable Valve Duration (CVVD) technology to feature in future Hyundai and Kia vehicles.
Previous variable valve control technologies could not regulate valve duration, as the valves closing timing was subordinate to opening timing and could not respond to diverse driving situations.
Engineering improvements include the first commercial application of Continuously Variable Valve Duration (CVVD) technology.
It was concluded that the best intake valve duration was that of the baseline engine, while reducing the baseline exhaust valve duration by 10% was optimal.
The 1.6-litre T-GDi engine incorporates an array of new technologies, including Continuously Variable Valve Duration (CVVD), which continuously adjusts the inlet and exhaust valves' opening times, optimizing the timing to suit all engine speeds and conditions.
* Freedom to command valve durations as short as 40 degCA at 1500 r/min,