Variable Valve Control
Encyclopedia
VVC is an automobile
variable valve timing
technology developed by Rover
and applied to some high performance variants of the company's K Series 1800cc engine.
In order to improve the optimisation of the valve timing for differing engine speeds and loads, the system is able to vary the timing and duration of the inlet valve opening. It achieves this by using a complex and finely machined mechanism to drive the inlet camshafts. This mechanism can accelerate and decelerate the rotational speed of the camshaft during different parts of its cycle. e.g. to produce longer opening duration, it slows the rotation during the valve open part of the cycle and speeds it up during the valve closed period.
The system has the advantage that it is continuously variable rather than switching in at a set speed. Its disadvantage lies in its complexity. Other systems achieve similar results with less expense and better reliability.
For a more detailed description, see the sandsmuseum link below.
The VVC engine is also fitted into these non MG/Rover cars:
Ariel Atom
, Lotus Elise
, Caterham 7, Caterham 21
, GTM Libra
Automobile
An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...
variable valve timing
Variable valve timing
In internal combustion engines, variable valve timing , also known as Variable valve actuation , is a generalized term used to describe any mechanism or method that can alter the shape or timing of a valve lift event within an internal combustion engine...
technology developed by Rover
MG Rover Group
MG Rover was the last domestically owned mass-production car manufacturer in the British motor industry. The company was formed when BMW sold the car-making and engine manufacturing assets of the original Rover Group to the Phoenix Consortium in 2000....
and applied to some high performance variants of the company's K Series 1800cc engine.
In order to improve the optimisation of the valve timing for differing engine speeds and loads, the system is able to vary the timing and duration of the inlet valve opening. It achieves this by using a complex and finely machined mechanism to drive the inlet camshafts. This mechanism can accelerate and decelerate the rotational speed of the camshaft during different parts of its cycle. e.g. to produce longer opening duration, it slows the rotation during the valve open part of the cycle and speeds it up during the valve closed period.
The system has the advantage that it is continuously variable rather than switching in at a set speed. Its disadvantage lies in its complexity. Other systems achieve similar results with less expense and better reliability.
For a more detailed description, see the sandsmuseum link below.
The VVC engine is also fitted into these non MG/Rover cars:
Ariel Atom
Ariel Atom
The Ariel Atom is a high performance sports car made by the Ariel Motor Company based in Somerset, England and under licence in North America by TMI Autotech, Inc. at Virginia International Raceway in Alton, Virginia....
, Lotus Elise
Lotus Elise
The 1996 Lotus Elise weighed . Because of its relatively low weight, it was able to accelerate 0- in 5.8 seconds despite its relatively low power output of...
, Caterham 7, Caterham 21
Caterham 21
The Caterham 21 is a two seat roadster designed and hand built by Caterham Cars. It was intended to be a more standard styled version of the Caterham 7....
, GTM Libra
GTM Libra
The Libra was launched by GTM Cars Ltd on the UK kitcar market in 1998. Three years in development it was a collaboration between GTM Cars directors Peter Beck & Paddy Fitch, designer Richard Oakes and suspension designer Bryn Davies....