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Not in the long run. Only the electric motors can power the car in reverse. As soon as your traction battery ran out of juice, the ICE would come on to provide the electricity. This is a less efficient way to power the car than having the ICE turning the wheels itself and storing any extra "waste" energy to the battery.
 

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littleboy said:
Would driving in reverse improve my gasoline mileage in the Prius?
That is known as "rmpg". According to Einsteins theory of hybrid relativity, if two relatives are driving Prii, moving in opposite directions towards one another at the speed of light, there is zero chance of rmpg. :?
 

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Discussion Starter · #5 ·
An04Prius said:
littleboy said:
Would driving in reverse improve my gasoline mileage in the Prius?
That is known as "rmpg". According to Einsteins theory of hybrid relativity, if two relatives are driving Prii, moving in opposite directions towards one another at the speed of light, there is zero chance of rmpg. :?
Thanks for "clarifying" that issue for me.... :lol:
 

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Driving in reverse (WITH the beep left on) is appropriate in fall. Drive in reverse for one hour pre-dawn on the last Sunday of October, in order to turn time one hour back. This relates to the space-time continuum that was discussed in a previous thread that Ken started. Be careful, however. You could end up in 1942 Nebraska. It's a delicate thing. :wink:
 

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Discussion Starter · #7 ·
Sanny said:
Driving in reverse (WITH the beep left on) is appropriate in fall. Drive in reverse for one hour pre-dawn on the last Sunday of October, in order to turn time one hour back. This relates to the space-time continuum that was discussed in a previous thread that Ken started. Be careful, however. You could end up in 1942 Nebraska. It's a delicate thing. :wink:
Would this "theorem" be correct: MPG in a Prius is inversely related to the direction of the movement? :wink:
 

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wayneswhirld said:
redwein said:
Only the electric motors can power the car in reverse.
When I start my car in the mornings and back up in my driveway, the ICE runs.
Start the car, wait for the warmup to complete so the ICE stops, THEN see how far you can go in reverse before you need the ICE again...
 

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wayneswhirld said:
redwein said:
Only the electric motors can power the car in reverse.
When I start my car in the mornings and back up in my driveway, the ICE runs.
That is only to warm up the engine and catalytic converters. Even when the engine is on, it is not capable of moving the car in reverse.
 

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Discussion Starter · #11 ·
redwein said:
wayneswhirld said:
redwein said:
Only the electric motors can power the car in reverse.
When I start my car in the mornings and back up in my driveway, the ICE runs.
That is only to warm up the engine and catalytic converters. Even when the engine is on, it is not capable of moving the car in reverse.
Intriguing....why is the ICE incapable of moving the car in reverse? :?:
 

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I don't know the details, but the particular planetary gear arrangment determines this. In other words, which inputs/outputs (ICE/MGs/final drive) are connected to which gears (ring/planet/sun) probably would require the ICE to spin backward to back up. The electric motor can spin forward or backward, but an ICE cannot.
 

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REVERSE MPG

Wouldn't the odometer run backwards if your car is in reverse? So if you went 1 mile in reverse, your MPG would also be negative, (e.g) -50 miles per gallon. Or does the Prius' odometer run forward, even if the car is in reverse?
 

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I can't say that I've driven far enough in reverse while also looking at my trip odometer (looking behind me, for safety!), but I do know that the spedometer shows speed in absolute value (no + or -). I know some people who have had fun taking people out in their Classic Prius, and floor it in reverse in an empty parking lot or straight road, to show off the torque of the electric motors, and they'd get up to about 35mph rather quickly in reverse before they run out of room or their passengers are too white-knuckled...

As for the reverse thing:
http://www.ecrostech.com/prius/original/PriusFrames.htm
Go to "Understanding your Prius"
Go to "What's Going On As I Drive?"
and scroll down to the bottom for the "Reversing" section.
 

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littleboy said:
redwein said:
wayneswhirld said:
redwein said:
Only the electric motors can power the car in reverse.
When I start my car in the mornings and back up in my driveway, the ICE runs.
That is only to warm up the engine and catalytic converters. Even when the engine is on, it is not capable of moving the car in reverse.
Intriguing....why is the ICE incapable of moving the car in reverse? :?:
An ICE only runs in one direction. In a normal car, there is a transmission which, through gearing allows the engine moving in a single direction to push the car in either direction, depending on whether you are in a forward or reverse gear. You physically "shift" the transmission to accomplish this. An electric motor, can go in either direction. In the Prius, there is no geared transmission that can be used to apply power in the opposite direction from the way it is spinning. So when the car is in reverse, only the electric motors are actually powering it. If the ICE is on, it is either just warming up or generating electricity. I'm sure this isn't the best description possible but I think it gets the point across.
 

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Try these 2 sites:
Simulator: http://www.wind.sannet.ne.jp/m_matsu/pr ... Country=US
Description of how it works: http://home.earthlink.net/~graham1/MyTo ... Frames.htm

As for speedometer, it works by pulses that are correlated to wheel rotation, unlike a conventional mechanical speedometer that uses a coupling of a spinning magnet inside a metal cup, where the cup torque correlates to the spin of the magnet, which correlates to the rotation, including direction, of the wheels.

The fact that the pulse is unrelated to the direction of rotation is why NAV and the MFD both need information that the car is put into reverse.
By the way, did you notice the wheels in the display turn the opposite way when in reverse?
 

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KTPhil said:
I don't know the details, but the particular planetary gear arrangment determines this. In other words, which inputs/outputs (ICE/MGs/final drive) are connected to which gears (ring/planet/sun) probably would require the ICE to spin backward to back up. The electric motor can spin forward or backward, but an ICE cannot.
Would this still be true when the moon is in the seventh house, and Jupiter aligns with Mars. I see the Dawning of the Age of Aquarius.
:lol:
 

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wayneswhirld said:
When I start my car in the mornings and back up in my driveway, the ICE runs.
redwein said:
An ICE only runs in one direction.
Well, tonight when I arrived home after my 40 mile commute (engine fully warmed up), I put my car in reverse for 100 feet or so and..........the only sound was the reverse beep. So it's good to know my Prius is normal :)
 

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SgtKarl said:
Would this still be true when the moon is in the seventh house, and Jupiter aligns with Mars. I see the Dawning of the Age of Aquarius.
:lol:
oooooo!! Peas will guide the planetary motion...
 

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Sanny said:
ooooo!! Peas will guide the planetary motion...
I much prefer peas to war. I'm a peas-nic.
 
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