High Quality Content by WIKIPEDIA articles! The Valvetronic system is a variable valve timing system to offer continuous and precisely variable intake valve lift, from ~0 to 10 mm, and duration. It typically works in conjunction with the independent Double VANOS system that continuously varies the timing (on both intake and exhaust camshafts). Valvetronic-equipped engines rely on the amount of valve lift for load control, 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.