....eeeh, not quite. I know for
sure that the valves deactivate, too. That's why they have trouble putting it in some engines, not enough space in the valley for all the crap to make it work. And I distinctly remember arguments about the backpressure created, because the valves were closed - people count figure out what the point of it was.
But you did get me on one point...the little cyllinders are not on the camshaft, the pushrods
are always touching it, the "De-ac" lifter is in between the lifters and the pushrods, my bad.
Interesting read on the LS4 (you'll have to scroll down a bit):
LS4
Quote:
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The keys to AFM’s efficiency are advanced capabilities built into the ECM and a set of special two-stage hydraulic valve lifters. These De-ac lifters are installed for cylinders that shut down in V4 mode. They have inner and outer bodies which normally operate as a single unit. When the engine controller determines cylinder deactivation conditions are optimal, it activates solenoids in the engine lifter valley, which in turn direct high-pressure oil to the switching lifters. This oil pressure activates a release pin inside the lifter, allowing the outer body on the De-ac lifter to collapse around the inner body. The shortened lifters move with the camshaft, but do not move the pushrod or operate the valves on their cylinders. When the ECM wants V8 power, it stops the flow of oil to the De-ac lifters. The locking pin releases and all valves begin operating.
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