Gen 4 Staff Manual (In Japanese) =/ Specs/Design/Other Info

we do exactly how? The test results are not out yet

 

as I recall reading about TNGA, it is designed to be compatible with both double wishbone and twist beam.
2nd, the reports said that Gen4 will have DWB. So did reports on Altrus. Only when it was released we found out lower trim was fitted with twist beam.

 

Is this nightmare really becoming true ?
I always thought Toyota could do magic,but getting better milage by significantly reducing system power output is far from it !
I must say I am really disappointed, so this seems to be the end of their magical Hybrid Synergy Drive .
They don't longer seem to be able to achieve better efficiency and increasing power at the same time !
I was expecting a way more powerful Prius this time,but as it appears this is not going to happen!
It will be about the same .
The only promise Toyota seemed to have kept is better mpg but what happened to "lighter" and "more powerful" ?
I still hope they just fell for false data in that freaking manual !

 

I suppose the main issue they ran into making TNGA-based car 20% lighter. The hybrid power output was right on target for lighter car.
They needed to get Prius weight down under 2,500lbs, to what Prius C weights.
That turned out to be unrealistic without use of exotic materials and downsizing.

 

"The maximum output of the entire system is 90kW, which is lower than that of the previous Prius (100kW). However, the driving performance of the new Prius is equivalent to that of the previous model because of the improvement of energy efficiency,the company said . "

So why would Toyota even talk to them and ruin everything they worked so hard to keep secret so far ?
They haven't talked to anybody else,so why are they the chosen ones ?
Why was Toyota being so anxious of people looking under the hood ?
Why even bother hiding things,and then coming clean just a few days later before big Showdown in Tokyo ?
Sounds to me they are just referring to the hopefully false data of the staff manual !

 

Damage control?

With Gen4 you can say that you are getting uglier car which weights the same, has less power and only marginally better fuel economy. Is it cheaper than Gen3 then? Not with discounts they were blowing Gen3 left overs.

 

you can say that, but it's opinion, not fact.

 

I'm not sure if everyone understands, but peak horsepower ONLY affects top speed. How many of you drive your car at 160 km/hr plus?

Torque is what we feel as "power". A car with lots of torque feels very powerful. You can have torque at lower RPMs (where we usually operate our cars) WITHOUT high HP.

Designing the car to provide lots of torque at lower speeds and less peak HP will give better mileage. Though in my experience, it causes the driver to enjoy "zipping around", which will lower mileage.

 

That is absolutely false.

So is that.

That's for a historical reason having nothing to do with modern cars with CVTs.

What we feel as power is acceleration. Acceleration goes with power output to the ground, not torque generated at the crank shaft. You could have a car with a million foot pounds of torque and only 1 horsepower, and you would feel the same acceleration as if you had an 18,000 RPM 1HP engine with different gearing.

 

Just one correction: Torque "at the wheels", which isn't the Torque usually found in engine data sheets, but it's that value multiplied/demultiplied by the gears ratio. That's why in lower gears the car has more "power" than in higher ones.
And we still know nothing about the new PSD ratios.

 

[/quote][/QUOTE]
I don't think so. Here is the way I see it.

What we feel as power is primarily acceleration of the car and rate of increase in that acceleration. (Noise, vibration and other subjective effects also have some influence)

Acceleration and its rate of increase go with increase in force delivered to the vehicle.

With conventional vehicles there is a matching reactive force in the opposite direction delivered to the ground. (Does not apply to planes even when they are on the ground)

The faster you go, the more power is required to maintain the force delivered to the vehicle.

There is no power output to the ground except to the extent that you move the ground (spraying gravel). To the extent that this happens, you lose corresponding acceleration.

If you lose traction, then you lose your anchoring force, your force delivered to the vehicle and your acceleration.
Torque is rotational force and rpm is rotational speed.

At maximum speed you have zero acceleration (otherwise it wouldn't be maximum speed). Assuming suitable gearing, at maximum speed, you are limited by maximum power delivery)

 

what is not true? That it has less power? Or it doesn't weight 20% less than Gen3?

 

you'd better look at those Prius dynocharts. HSD is doing great job in keeping car at max power from 30mph up

 

Yes, I said that:

Yes, and the force delivered to the vehicle is equal to power/speed. And acceleration is force/mass. So, acceleration = power / (mass * speed). Again, what we feel goes with *power*, not torque.

Now torque delivered to the drive wheels, as stated above by Alesf76 goes directly with acceleration (we're ignoring drag all along here, as that's another issue and generally not very important for things like 0-60 times). However, torque delivered to the drive wheels = power / wheel speed. So, again, it's power that's driving the acceleration.

The historical reason torque was thought of as power was that the gear ratios were fixed, including the final drive ratio. It was a common trick to increase the final drive ratio to get faster acceleration and thus better quarter mile or 0-60 times. But that's because you could get the engine to a higher RPM where it has more power at a lower speed, and then up shift as necessary to keep it near that power peak as you accelerated. But with a CVT, especially one with electric boost, that's less of an issue. You can get closer to peak power faster and you can hold it there more accurately using such a system.

The other historical reason people focused on torque is that a higher peak torque was necessarily associated with a flatter power curve versus RPM. Again, technology has largely eliminated this issue, both because of the CVT and because of variable valve timing.

So, the old hot-rodder axiom that it's the torque that matters doesn't hold true for cars with modern drive and engine technology.

 

we don't know if anything in this manual is 'true', until we have a car and official toyota usa specs.

 

I think this is the most official and committed-to-paper-and-distribution info we have on the subject so far, and I would accept it as being the most-probable truth until something better shows up.

Finding reasons to justify it as un-truth seems desperate in the absence of credible evidence to the contrary.

 

i said, 'we don't know'. that is not denial, it's keeping an open mind. trying to interpret information in negative ways before knowing all the facts is simply bashing from haters.

 

thanks, that has been my plan all along.

 

Ref. (http://www.ae.pwr.wroc.pl/filez/20110606092430_HEV_Toyota.pdf)