How Fast In Reverse ?

[kithmo]

Is there a limit to the speed one can travel in reverse gear in the Prius, or does everything just work the same backwards as forwards ?

Not that I'm entering a reverse race or anything, just curious.

[timberwolf]

Is there a limit to the speed one can travel in reverse gear in the Prius, or does everything just work the same backwards as forwards ?

Not that I'm entering a reverse race or anything, just curious.

The design of the transmission has a bias towards going forwards, i.e. the Petrol engine can only provide forward motion directly. Reversing is solely provided by the Motor Generators, although the petrol engine can provide energy via one of the Motor Generators on the Gen 2 and 3 design but not Gen 1 if I recall correctly.

[Doesn'tExist]

Is there a limit to the speed one can travel in reverse gear in the Prius, or does everything just work the same backwards as forwards ?

Not that I'm entering a reverse race or anything, just curious.

Ah Thatcher brought back fond memories of my old Daf :-)

[Ancient Nerd]

Is there a limit to the speed one can travel in reverse gear in the Prius, or does everything just work the same backwards as forwards ?

Not that I'm entering a reverse race or anything, just curious.

Ah Thatcher brought back fond memories of my old Daf :-)

Ah yes, the DAF. I once bought a Volvo 66 for my wife to use. She's a bit of a nervous driver, so I took her to an empty car park to get used to the car before going on the road. I parked the car facing a wall.

It was when she got in, put it in reverse and backed out that we discovered it went the same speed backwards as it did forwards. :eek:

[BlueValour]

Is there a limit to the speed one can travel in reverse gear in the Prius, or does everything just work the same backwards as forwards ?

Not that I'm entering a reverse race or anything, just curious.

Ah Thatcher brought back fond memories of my old Daf :-)

Ah yes, the DAF. I once bought a Volvo 66 for my wife to use. She's a bit of a nervous driver, so I took her to an empty car park to get used to the car before going on the road. I parked the car facing a wall.

It was when she got in, put it in reverse and backed out that we discovered it went the same speed backwards as it did forwards. :eek:

You are lucky she didn't try out the forward speed.

[DrCez]

Is there a limit to the speed one can travel in reverse gear in the Prius, or does everything just work the same backwards as forwards ?

Not that I'm entering a reverse race or anything, just curious.

I tried it at http://eahart.com/prius/psd/ and according to the simulator you can travel at up to 25 mph backwards! This simulator applies a maximum limit of -1462 rpm on MG2 (MG2 = motor/generator 2, the larger of the two motors in the Prius hybrid synergy drive). If it were allowed to spin faster than that (and I don't see any technical reason why not other than the fact that some idiot driver might try it! ) then the next limit would be 42 mph which is also the maximum electric-only speed going forward, and corresponds to MG1 reaching its maximum allowed speed of 6500 rpm.

Interestingly if the petrol engine (ICE) is running then the maximum reverse speed is -19 mph since MG1 has to spin faster to counteract the "forward" rotation of the ICE and so reaches its limit sooner. The ICE would be needed if the HV Battery charge was low or there was a big demand on the motors (e.g. hard acceleration/steep hill). So if you're ever in a reverse Prius drag race make sure your Battery is fully charged, select EV mode and make sure you don't accelerate too hard - sure the other driver might pull away faster but they will hit the limit at -19 mph allowing you to silently pass on electric power travelling at least 6 mph faster

[johalareewi]

You won't go backwards at 25mph for very long before the ICE kicks in to generate some electricity.

[acetip]

You won't go backwards at 25mph for very long before the ICE kicks in to generate some electricity.

how fast sideways.

[kithmo]

Interestingly if the petrol engine (ICE) is running then the maximum reverse speed is -19 mph since MG1 has to spin faster to counteract the "forward" rotation of the ICE and so reaches its limit sooner. The ICE would be needed if the HV battery charge was low or there was a big demand on the motors (e.g. hard acceleration/steep hill). So if you're ever in a reverse Prius drag race make sure your battery is fully charged, select EV mode and make sure you don't accelerate too hard - sure the other driver might pull away faster but they will hit the limit at -19 mph allowing you to silently pass on electric power travelling at least 6 mph faster

LOL, now you've gone and done it !

Now I'm going to have to have a reverse drag race to check this out.

Mmmm.....maybe my colleague at work with his new Auris hybrid . . . . .

[Dave R.]

Just LOVE that simulator at http://eahart.com/prius/psd/

It continues to freak me out trying to understand how 2 electric motors and the petrol engine can work like that, & how the power can be controlled. Isn't Fly By Wire wonderful!