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Irace86.2.0
The problem with Freevalve is actually more about power consumption. All of the energy compressing the valve spring is lost, whereas with a cam drive you can recover a good portion, which becomes significant as the engine speed and valve lift increase. This is made worse by the fact that generating compressed air or pressurized oil is not efficient.
You don't need high valve lift most of the time so it's not that bad, but it still makes a dent on fuel efficiency. Additionally, since valvetrain power becomes a consideration, at moderate to high engine speeds using higher valve lift would reduce pumping losses, but it would increase valve actuator power consumption.
It turns out that fixed cam profiles really aren't as limiting as people originally thought. High EGR dilution ratios are by far the most important technique of improving part load efficiency, and you can cover the near-idle load scenario with cylinder deactivation or a second cam profile ala Honda/Porsche.
While chain driven cams probably are heavier than a Freevalve setup, I imagine a belt or gear driven overhead cam setup is actually lighter than Freevalve including the air pump.