Mountain driving

[priusdave]

now i dont own a Prius, but i do have my experiances in my friends prius

when we took a road trip in mammoth his prius made the 9,000 ft journey up to mammoth maountain. now this wasnt just an ordnary drive, we were lucky and we hit a large snow storm. no probd in the prius despite the ice and snow. 9.5-10

[jtmhog]

Consumer Union conducted a test where a Prius was driven slowly to discharge the battery, pink, and then driven up a steep incline. The car died in a short time. With a fully charged battery the car made it up the mountain going 55MPH with no problems. The test was conducted last year but, I couldn't find the article. Lesson learned: go up the mountain with a green battery and go the speed that keeps the battery in the blue. If you get in a bind, there is a solution--pull off the side of the road, put it in park and let the engine charge the battery.

[priusdave]

???? the motor can only go 42???? maybe im confused????

[gschoen]

jtm, I remember reading a similar article, but about either the Civic Hybrid or Insight (Couldn't locate article on CR website, can't even remember for certain if they wrote it).

Regardless, even if you do completely exhaust your battery (difficult to do as reported here), your speed would just be reduced and the battery recharged as soon as conditions allowed. There is no need to stop the car or put it in park, just drive it! (Even with a completely discharged battery, the system can still get torque if needed from the motor by generating elec directly off the engine - a big advantage IMA systems can't provide!)

Indeed, to get the conditions you described is very difficult on the Prius, as you discharge the battery more and more, the system uses the battery less and less. Stealth mode is gradually reduced and two bars is about the lowest you can go without sustained full throttle acceleration (before you hit the mountain, at least)

Most climbs don't keep the grade constant the entire time, the system gets a chance to charge up on these flatter portions.

[Steve Goldenberg]

On long, steep climbs even a "green" battery will deplete in just a few minutes if you're going fast (60+mph). A subtle side effect is that as the electric assist fades, the gasoline engine has to rev up more to make up the missing power.
When that happens, the CV transmission really gets noisy because when the electric motor side of the planetary gear system slows down, the other side has to speed up. When both sides are at equal RMP's, the drive noise is much less. I think that's where the speed limit on gas only, enters the equation.
A turbo would really solve the problem.

[energy1]

I am on vacation right now. One of the objectives was to go up Pikes peak, over 14,000 ft. I had no problems at all. Down to one purple bar on the way up. All green bars on the way down. ICE only came on twice, while climbing slight uphill. Approx 35 mpg up and down.

Ron

[Steve Goldenberg]

If ICE means Internal Combustion Engine, then it's iimpossible that it only came on twice on the way UP to Pikes Peak. It might have gone OFF twice but almost all the power would have to come from the ICE and it would be on all the time you were going uphill. It could well have been OFF on the way down.

[NuShrike]

From the game GT4, the Prius can maintain a speed of ~75mph with a drained battery on mostly flat level ground.

That's pretty good because that's above most usa speed limits.

Also, this means the car can never die on the road. I don't think these 'tests' of the Prius dying and not being able to move with a drained battery even on inclines are valid unless it's some high torque test at low speeds of which the ICE is not designed to be very useful nor powerful.

The Prius without battery assist drives like a Geo Metro probably, but there's still 67hp usable there.

[Stocky]

Sure - I did have the luxury of downhills to give the battery a little tickle up, so that is probably why I got such good performance.

I guess your US roads are probably better than those I was driving on, as it would have been sheer suicide to travel anywhere near 100km/h (60mph) - LOL

[DanMan32]

<div class='quotetop'>QUOTE(energy1\";p=\"90427)</div>

ICE only came on twice, while climbing slight uphill. Approx 35 mpg up and down.

Ron
[/b]

Correct me if I am wrong Ron, but I believe he meant the ICE only came on twice on the way down, due to slight uphill at some points.