Because of the lower volumetric efficiency, the initial throttle openings for the start and idling of the LPG engine are larger than those of the gasoline engine.

由于较低的充气效率，发动机使用LPG燃料成功起动时的初始节气门开度及能够稳定在怠速转速下的节气门开度比使用汽油燃料的大。

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Adopt measure to prevent the heat transmit between intake pipe and exhaust pipe, lower the intake air temperature to increase volumetric efficiency.

采取进、排气管隔热措施，降低进气温度来提高进气充量。

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