If Prius has to constantly spin the ICE when over 42 mph, even when only running on battery power, it must waste a lot of energy overcoming ICE compression all the time. Or is there some kind of system to reduce compression in this situation – just curious
I wager that the North American market Gen II ICE will run continuously above 41 mph with your foot on the gas. Coasting, different story. Still, I believe EV is not possible above 41 mph without ICE engaged, and that would not be EV. Interesting though, wonder if the variable valve timing, intelligent (VVTi) has an open valve position. Somebody must know.
Think of the cylinder as a spring, while it takes work to compress it, you get almost all that work back on the decompression. Altering the valve timing is possible.
Does the gen 2 Prius have VVT-I, mine is described as VV-I but I don't know what that stands for or means?
It is a Toyota buzzword, Variable Valve Timing, with Intelligence. You have seen Hobbit's chart so you see it is not just based on RPM. VVT-i - Wikipedia, the free encyclopedia Gen 1, Gen 2, and the c uses variations of this engine, all with VVT-i Toyota NZ engine - Wikipedia, the free encyclopedia
I suspect VV-i of being the buzzword in nations where VVT-i was already a trademark for some other company.
Amazing technology, Toyota's VVT-i.....seriously, if the "I hate Prii brigade" stopped for just one minute to investigate what really makes Prii tick, and makes them so unique and irresistible to us savvy owners.....they'd learn about one of the world's greatest motoring secrets.......and stop creating inane myths about it.
So is the Prius engine able to pretty much free-wheel with the engine running but no load? It feels very much like it's in Neutral, to me. My ScanGauge shows rpm (around 900) and zero fuel consumption, fwiw.