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Old 10-26-2012, 11:13 PM   #36
Coheed
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Quote:
Originally Posted by arghx7 View Post

The Prius uses late intake valve closing Atkinson cycle. It controls engine load using valve timing instead of a throttle valve. It also means that the compression ratio is lower than the expansion ratio.
Prius works just like a regular otto cycle. It just has late valve opening like you said. But it still has a throttle valve, as seen in this pic. As you can see, VE is also affected by its small size.


I don't consider this a real "atkinson cycle" because it is far from his designs, but the modern concept works almost identical, and is much simpler.

Its a beautiful thing. They close the intake valves late to push extra intake air back out of the cylinder. This limits the actual VE of the engine.
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