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Back around 2003-2006 I looked into V-Tech which was using a variable cam lobe with a more agressive profile that engaged when "needed". Today, we have motors with a continuously variable valve timing and no cam at all. Are V-Tech motors still in production and if so, do they still use the same technology or have they moved to a variable, cam-less setup?

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cam-less?? I know they've eliminated lifters, but without cam, how do you open valves? Unless you are talking about an electric motor. Btw, all continuous variable timing that I've ever seen is done by having rotation axis between the cam and the gear that is driven by the timing chain. Then they typically use oil pressure to change the position of the cam relative to the gear. –  DXM Jan 11 '12 at 0:03
    
There are both electromagnetic and air pressure valve actuators that do not require a cam. I do not believe that any of them are in road-going production cars. I believe I once heard that at least some of the F1 race engines used the air activated system? –  Brian Knoblauch Jan 11 '12 at 12:55
    
@DXM yes I see that now. I misunderstood a GM video explaining the new Cruze 1.4l turbo packages which have VVT using a hydraulic system to adjust the cam. –  DustinDavis Jan 11 '12 at 15:26

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i-VTEC is definitely camshaft based - it does have the ability to vary the intake came quite a bit. Honda has submitted the patents for AVTEC but has not yet put them into production.

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