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Old 11-20-2022, 04:47 PM   #27 (permalink)
Ecky
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Quote:
Originally Posted by hayden55 View Post
So you have your BSFC g/kWh graph with the islands of efficiency. Basically the car can target that super high efficiency island the entire time (a certain rpm and load and torque output), which makes up for the extreme loss the eCVT gives.

I would say eCVT efficiency is around 85% and DCT is around 91%+ efficient.

I imagine if you just dyno'd a prius and ioniq new after break in on a dyno the same day you will see around the efficiency difference.
Where do the eCVT inefficiencies come from? I sometimes find planetary gears with multiple inputs hard to wrap my head around. It's my understanding that the electric motors need to provide some torque against the engine to get some of the ratios, but there are no frictional losses you wouldn't have in a DCT or manual.
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