Patent ID: 7530922

Claim:
An engine control apparatus of an engine in which an output shaft is connected to an automatic transmission or a manual transmission with an automatic clutch, comprising: an MBT ignition timing determining portion which determines, based on an operating state of the engine, an MBT ignition timing that generates maximum torque in that operating state of the engine; a target torque-down rate determining portion that determines a target torque-down rate which is a ratio of a target torque of the engine when a speed of the transmission is changed to the maximum torque; a target ignition timing determining portion which determines a target ignition timing for achieving the target torque-down rate based on the MBT ignition timing; and an ignition control portion which executes ignition at the target ignition timing; wherein the target ignition timing determining portion determines a target retard rate from the MBT ignition timing which will achieve the target torque-down rate and determines the target ignition timing based on the target retard rate.