[QUOTE=yudlose;246812]I've done the same thing. Here is a pic of the speedo at ~52 mph in EV mode.

It's a neat feeling coasting along like a roller skate sometimes passing up other cars that are going slower than you. It was easy to see my car actually speed up rather quickly in neutral as some of he 1/4 mile stretches were rather steep coming down that mountain. It was a 4-lane divided highway for the entire 15 mile coast to east side of Tularosa, New Mexico.

 

So, if I understand correctly, the reason for going into neutral is to keep the ICE from starting at all at over speeds of 40 mph? As well as prevent regen breaking from slowing the car?

 

No, and Yes.

At about 42 mph in the Prius, and 48 mph in the Camry the ICE has to spin to prevent the electric motor generator (MG-1) from going into overspeed. The way the transaxle is designed there is no way to prevent this. Having the ICE spin even though there is no fuel going to it still makes it a brake that is sucking energy. The best way to understand it is to play with the sliders in this Hybrid Synergy Drive Simulator.

Leave the ICE at zero rpm and then slide the speed up to about 45 mph and see what happens.

If you put the Selector switch in "Neutral" the motor generators are electrically isolated and cannot act as a brake or a motor. However they still spin and suck energy. There really is no neutral in a Toyota Hybrid Synergy Drive. It is really important when towing a Toyota Hybrid to always get the front wheels off the ground. If you don't then you can overspeed the motors and destroy them, even though the TX is in "neutral".

The result is that Pulse and Glide in a hybrid is rather ineffective. It does work in a conventional vehicle, but is kind of a dumb and dangerous way to drive if you share the road with other vehicles.

 

Yeah, I've never really done the neutral thing and certainly not turned the car off on cenventional.

That simulator is awesome... I'll have to look into that... great depiction of how it puts everything together. I don't really understand how MG1 and MG2 work together with the ICE... time for some reading!

 

This is a reasonably readable article on how it works. This is mainly intended to apply to the Prius, but most of it applies to the Camry too.