stealth or not stealth

It's not a technical term! People can define it differently if they want. I'd call that "coasting", myself. Stealth, to me, means the car's running silently, which means that the ICE is off.

Personally, I try to keep the car coasting (if I think I'll need to slow down soon) or running on battery (amber arrows, if I think I'll need to maintain or increase speed). The battery recharges itself pretty efficiently even when I knock it down a few bars, and my mileage is up since I've been doing this (though it's also warm out, which I'm sure is a larger factor)

 

For me, coasting is moving forward without your foot on the gas pedal and stealth is moving forward under electric power.

 

The ability to coast was extraordinarily rare with the classic Prius (when the term "stealth" was first coined), so it's frequent emergence on the 2004 is naturally a bit confusing.

Personally, I rarely use the "Energy Monitor". Not having MPG on that screen originally made it far less useful than the "Consumption" screen. So I don't use it often. "Consumption" has that immediate-bar that is remarkably easy to see with just peripheral vision and I like watching that MPG average slowly climb up. In short, I don't know when I'm coasting anyway.

As for stealth, that is when the engine is stopped (not just off) and you are powering the wheels exclusively with electricity. So coasting (working the "deadband") is part of stealth, just like regen is.

Then there's "warp stealth". That's when the engine shuts off but remains spinning, like when you drive down a hill on a highway.

 

Fred, like you I only drive 10 minutes most times. You and I are being more green, not less green than the others. Our mpg is lower, due to the greater percentage of time spent in Phase I, but overall we are burning less gas and producing less pollution. Most green is making lifestyle choices that require less driving.

 

I've got a techie question for what exactly "warp-stealth" or "hyper stealth" is - I understand that the ICE is 'spinning' without running, but what exactly does that entail? Does it mean that the pistons are pumping without gasoline injected? I'm not really concerned about if the engine can handle it - I've got faith in it, but I'm just curious to how it works. Anyone who can enlighten me on this topic would be greatly appreciated.

-m.

 

The Atkinson-cycle engine has the ability to leave the valves open and spin with virtually no resistance, no spark, no fuel.

 

rflagg,

now that I have observed my new prius a little more, I noticed that the two modes (stealth and W-Stealth), actually consist of 3 modes. To be more exact, the Electric Motor (MG1) knows three conditions. 1. acceleration. The #1. is referred to as stealth mode, since the only propulsion desired here is electric only. The 2 stage is the one where neither the arrows show up green, or amber and all the electro motor does is keeps it self going. The third mode is the mode where the MG1 is used as slow down, or perhaps the arrows are ohly green to charge the batteries. This last mode, at higher speed (>42 mls/hr) will have still the ICE engaged some what, which I have not 100% confirmed for that I wish the Prius had an RMP meter for the ICE only. The reason why I say that is simple, when you put the car on a decent in "B", you will actually hear the ICE spin up as if you had shifted down. But what happens when the Battery is all "Green", whell now is that stage reached where no more effect is achieved by the ICE to regenrerate, and to cause deceleration (engine breaking), now the ICE spins up in the max RPM range, in efforts to introduce mechanical resistance.

----------- hope that helps --------- Ralph