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      10-16-2009, 05:57 PM   #73

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Originally Posted by adc View Post
To sap means to waste.
Oh I see.

The mechanical linkage of an electric motor to the turbo shaft does not necessarily imply that energy would be wasted when the motor is not operating. At lower rpms the electric motors would run the turbo and at higher rpms exhaust gasses would take over. If a one-way shaft bearing is used then the electric motor will run freely on the turbo shaft at higher rpms i.e. energy will not be wasted in dragging the electric motor (there will only be some minor frictional bearing losses). Not sure if I make any sense...