Why is it that on our (SC400) we lose so much in drivetrain loss? Anyways, is there something we can do to minimize the loss?

 

Combination of the weight of the drivetrain and all the gears and joints that each loose efficiency. Automatic transmission cars with RWD and IRS have the highest percentage drivetrain loss. Cars engineered to be smooth and quiet give up some power for isolation.

Big heavy torque converter, big strong but heavy automatic transmission, multi-piece driveshaft with center support bearing and vibration isolation, strong differential with dual support bearings on the pinion, complex driveshafts with 2 CV joints per shaft, large wheel bearings to support IRS and tire/wheel/brake mass.