Originally Posted by smellthebeans
The Valvetronic system is the first variable valve timing system to offer continuously variable timing (on both intake and exhaust camshafts) along with continuously variable intake valve lift, from ~0 to 10 mm, on the intake camshaft only. Valvetronic-equipped engines are unique in that they rely on the amount of valve lift to throttle the engine rather than a butterfly valve in the intake tract. In other words, in normal driving, the "gas pedal" controls the Valvetronic hardware rather than the throttle plate.
It is important to note however, that the throttle plate is not removed, but rather defaults to a fully open position once the engine is running.
Pulled this from here
Makes sense to me
Wikipedia probably got that info from us at E90post.com.
Dinan took the OEM throttle body and widened it. The inner diameter is slightly bigger, as is the butterfly valve.
The new N52 and N54 engines use a ceramic material for the valve and a different triggering mechanism.