Originally Posted by mmarshall

Any Time.




Chevy itself uses the term VVT for the gas engine. Here's the literal spec from the web site:

• 1.5L Variable Valve Timing (VVT) with a Direct Injection (DI) DOHC 4-cylinder engine

Yes, the VVT-i (for intelligence) can sometimes get confused with the "i" for "injection". Thanks. It's a valid point. I'll correct the typo.





I tried to describe it pretty much the same way you that and Farah do. I paid a lot of attention to the drive-train during the test-drive (and there is a power-flow graph on the video-screen that tells you which engine is working, and now much, though there is no tach for the gas engine). The electric motors always drive the front wheels, though they are recharged by the gas engine as needed, You can hear the gas engine cut in and out, at cruise, without any bump or vibrations, because the gas engine's direct torque (or start-up) never reaches the wheels...it's all done through the electrics.

That's one thing I really like about this drive train...and why I spoke of it so highly. It offers full-electric smoothness and torque with gas-boosted range....pretty much the best of both worlds. I think GM really has something with this drive train....it's a shame that the same attention wasn't put into the rest of the car, but I guess that's one way they keep the price down.

Originally Posted by DP03

Perhaps the Volt will be different. The capacity loss on my Cmax was over 40% over 3 years, which to me is significant. I was using 220V charging, which is much faster than 110. But most plug in customers will tire of the long 110 charge time pretty quick.

Originally Posted by Sulu

That sounds no different from my ESh (and likely all other Toyota hybrids) which, apart from the much smaller battery, has a similar hybrid drive transmission to the Volt.

Originally Posted by mmarshall

I have't recently sampled a hybrid ES. Does it operate like the Volt does...pure electric-drive around-the-clock, with the gas engine simply recharging the big hybrid battery?

Originally Posted by mmarshall

Toyota/Lexus hybrids, of course, also come in two basic types. Some operate off of a transversely-mounted FWD layout, others with a longitudinal-mount RWD layout.

Originally Posted by Sulu

There is no difference in operating principles between the FWD-based or RWD-based Toyota hybrids.

Originally Posted by mmarshall

Perhaps that has changed, but there used to be. Some were strictly FWD through the front wheels; others had a separate electric motor on each rear wheel for an AWD effect.

Originally Posted by Sulu

No change in Toyota hybrid system operating principles since the start. FWD and RWD hybrid systems operate in the same fashion. FWD-based AWD systems merely added a single rear axle electric motor that is not connected to the main drivetrain consisting of the engine and Power Split Device (PSD) transmission; this is a form of the so-called through-the-road hybrid system.