[karl]

We may be getting a change of mind on this car--currently on the waiting list for a 2005... Is anyone aware whether the 2005 will have added horsepower? I accidentally high-centered my (work) Prius today while trying to back down a steep and serpentine driveway. With one wheel over the curb, it did not have sufficient horsepower to move forward from that position--like a standard auto would have. Had to get the help of neighbors to carefully back the car down a raised platform of planks supported by cinder blocks until the curb height was reduced enough for me to proceed forward and back down to the road. I also have noticed that the car can barely back up a steep driveway in reverse. Are you aware of any improvements in this area? Thanks!

 

[Ray Moore]

The Prius' speed in reverse is limited but it's torque is quite high and as long as you have juice in the battery that electric motor will pull you up a very steep hill. Let us know when you find one it won't climb. I think we'll be waiting a long time. The car is definitely not big detroit iron but that electric motor compensates quite well.

 

[karl]

Well, the battery was in good shape--had been doing a lot of highway driving. With the right rear tire hanging in mid air over the curb, I couldn't get the front wheels pull it forward at all--even floored it, but there was no forward movement. Let me know, if anyone has any further suggestions...

 

[RSnyder]

The Prius wheel slip limiting logic won't let the front wheels spin faster than the rear wheels. With one rear wheel in the air, perhaps this prevented it from moving forward?

It's very unlikely that there will be any powertrain differences in torque or horsepower between the 2004 and 2005 models.

 

[Knguyen]

hmmm? Some 67 pony on electric amotor at some 300ftlb at some low rpm plus some 76 standard mustang with some 80ftlb at some 4000rpm...
What do you mean you can't move forthward ? how steep was the incline ?.

I have 97 Camry with traction control and I have experience what traction control does when it kick.... which basically retard engine timing..to encurage me to consider the situation at hand and let go of the paddel...if not then (which I didn't)..it proceed to drop fuel delivery and made the engine really weak.. The wheel then slow to the point that both wheels catch up... all of which happen in about 3-6 seconds or so and I was out of the slippage situation due to engine drop out.

What I saying is even one of the rear wheel hang high... the front wheel..even due to traction control would still spin... it's is not spin madly but it still spin..slower than it should be.... the traction control logic would allow for a certain range of slipage between the left wheel and the right wheel and relative the the rear to keep the car moving forthward... otherwise the car would stop dead as soon as traction control kick in.

Now Karl say not sufficient horsepower to move forthward... I believe every one have seen the Geo Metro car right ?.....That car is a 1L 3 cylinders car...it can climb steep hills in Duluth Minnesota from stand still and it torque is a lot less than 300ftlb from the Prius electric motor.. and just a bit less from the 1.5L 80ftlb gas engine...How steep are we talking about here Karl. Even say the traction battery juice is so low that it can't provide full power as needed... what about the 1.5L gas engine...it's a have 80ftlb and 76 horspower .. I just can't imagine a 76 horse power can't pull it self out of "paved" steep road.... for the shake of comparison a 06 Corvete have some 400 pony and some 400 ftlb of torque... the Prius have some 300ftlb of torque .. That a lot of push...

Can you include some more info.. like did the ICU run?..did the Prius ok and any error message such as something damage?...did you hang the car as meaning that the car sit on the curve under it belly with one wheel hang in the air ?.. I mean if that was the case the wheel would smoke or would jerk as the traction control cut in and out...even for a normal car it would just smoke the tire if it didn't have traction control..or it would just grunt as the traction control cut power... but the car would still trying to move....what you post does not make sense.....either the car damage and dead in the water or something is amiss here...can you include more info....

 

[karl]

I don't recall the degree of incline we're talking about, but it was about as steep as you'd want a driveway to be. It may have just been a bizare situation which shouldn't affect one's overall perception of the car's abilities. The front wheels were probably spinning (I was inside pushing the pedal down), but there was insufficient power to pull the rear right wheel forward back over the curb. Basically, it would be like stopping the Prius on a steep incline and placing large blocks right in front of the rear wheels. Not that I intend to get into this scenario again, but is it possible a lower gear would have helped ("B")?

 

[RSnyder]

Not that I intend to get into this scenario again, but is it possible a lower gear would have helped ("B")?

Hi Karl,
B is not a lower gear. When your foot is off the accelerator, it simulates the extra engine braking you would get in a conventional automatic set in a lower gear. But it does not have any difference from D when you push on the accelerator. The larger electric motor (MG2) is directly connected to the wheels via a fixed gear ratio. Since it contributes almost all the torque at low speeds, there is no "lower gear" available that could have helped you with your particular situation.

 

[Knguyen]

Ok,

Sound like you got one of the rear wheel hang and one of the front wheel hang. In that case, I really think that you're stuck even with conventional non hybrid car. When one of the drive wheel hang, it will keep spin and cause the other drive wheel to stop dead. The traction control will only limit the speed of the wheel. Unless it have some thing call "posi-traction limited diffrential " thingy that keep one of the rear wheel spinning and the other one stop dead, I think you're stuck.

This situation really have nothing to do with whether the Prius sufficient horsepower on an incline or not but how one get out of a stuck situation like this.

 

[mdacmeis]

I don't recall the degree of incline we're talking about, but it was about as steep as you'd want a driveway to be. It may have just been a bizare situation which shouldn't affect one's overall perception of the car's abilities. The front wheels were probably spinning (I was inside pushing the pedal down), but there was insufficient power to pull the rear right wheel forward back over the curb. Basically, it would be like stopping the Prius on a steep incline and placing large blocks right in front of the rear wheels. Not that I intend to get into this scenario again, but is it possible a lower gear would have helped ("B")?

From this description, insuffient power would be inaccurate. If the front wheels were indeed spinning, you had insufficient traction to overcome the force needed to counter the affects of gravity and the additional friction experienced from a portion of the vehicle sitting on a curb instead of the tire, or the tire effectively acting as an anchor, if it was "hooked" on the other side of the curb. I suspect any number of vehicles would have reacted similarly under the same circumstrances.

 

[karl]

Ok,

Sound like you got one of the rear wheel hang and one of the front wheel hang. In that case, I really think that you're stuck even with conventional non hybrid car. When one of the drive wheel hang, it will keep spin and cause the other drive wheel to stop dead. The traction control will only limit the speed of the wheel. Unless it have some thing call "posi-traction limited diffrential " thingy that keep one of the rear wheel spinning and the other one stop dead, I think you're stuck.

This situation really have nothing to do with whether the Prius sufficient horsepower on an incline or not but how one get out of a stuck situation like this.

No... Only the right rear wheel was over edge.