摘要 |
A power controller is provided for a variable cam engine wherein an economy cam and power cam are changed over according to the running condition of the engine. To control engine power, the engine is provided with a throttle valve whose opening basically corresponds to the accelerator depression, but which can be varied freely independently of same. When a change-over is made between cams, the throttle valve is controlled to a target throttle opening such that the torque generated before and after the change-over is the same. At the same time, to prevent the occurrence of a torque shock when the economy cam is changed over to a power cam, the throttle valve is throttled to the target opening before the change-over is acutally made and the ignition timing is retarded taking account of the change-over period. Likewise, when a power cam is changed over to the economy cam, the throttle valve is opened to the target opening before the change-over is actually made, the ignition timing is retarded, but it is then returned to the original optimum ignition timing when the change-over period is reached.
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