摘要 |
This invention concerns a variable cam engine wherein cam change-over is performed according to the running condition of the engine. The engine is provided with a throttle valve whose opening basically corresponds to the accelerator depression, but which nevertheless can be freely varied irrespective of the accelerator depression. When a change-over is performed between the economy cam and power cams, a target throttle opening is computed such that the torque generated after the change-over is the same as the torque before the change-over. At the time, to prevent the occurrence of torque shock, the throttle valve is made to temporally overshoot the target opening, and then return to the target opening. The amount of this overshoot and the return time constant is computed based on at least the difference of throttle openings before and after change-over and the engine speed.
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