Intake control device and change condition setting method

摘要

The present invention relates to an intake control device for an engine (50) of a vehicle comprising a change control means (11a) for changing a length of an intake conduit (30) from a first length (L1) to a second length (L2) shorter than the first length (L1), and from the second length (L2) to the first length (L1), according to whether or not an engine speed has reached a predetermined threshold value, wherein the threshold value applied by the change control means (11a) has been predetermined on the basis of an engine output torque in the state of the intake conduit (30) set to the first length (L1) and an engine output torque in the state of the intake conduit (30) set to the second length (L2).