VTECIt changes cam duration at a point on the revrange, the engine has 2 cam profiles one better suited to lower end grunt the other to higher end grunt, when it switches from one to the other you get a 'boost' in power.
Personally I prefer the VVC system as it works throughout the rev range.
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Tue 15 Jun 2010, 9:59,
archived)
Personally I prefer the VVC system as it works throughout the rev range.