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

How did you get 6.2 in the first place? new Prius is 1,760 mm wide, 1470 mm tall, or 69.3" by 57.8'.
5' 9.3" by 4'9.8" give you 6.0 sq ft?

 

Yeah, scratch that. Looks like 6.2 was already CdA.

 

Yes it is. EcoModder has a list of the cars. Gen4 should have 6.0 CdA, 4% less

 

The other thing that can change drag A LOT is the rolling resistance coefficient of the tires (which itself changes with temperature). As I understand it, the one in Vegas had a newer version of the Bridgestone Ecopia than the ones that come on the 2015. If so, that could change mileage quite a lot on its own.

 

Nice, 20% more efficient in those mechanical and electrical paths. Some improvements in aero drag. 4-5% increase in ICE efficiency.

 

Car mileage is much, much less dependent on the peak efficiency of the engine than it is on the average efficiency over the driving cycle. If Toyota is able to hold it closer to the optimum point more, and if they are able to expand the width of the area around the peak, average efficiency could go up much more than the peak amount.

I did a study a long time ago, and in that case, a flat efficiency of 90% was better than a normal curve peaking over 96%. That was for something entirely different than this, but they are similar in the demands they place on efficiency.

 

Very true. Though it is hard them to beat now (sadly) discontinued Energy Savers. EP422 were only half way there.

When we switched from EP20 to Mich ES, MPG jumped up 2-3MPG.

 

Probably originally to differentiate engines with combustion internal to the engine from from steam engines with external combustion (in a boiler).

 

Yeah, akin to SLR, for Single Lens Reflex. It's long since triumphed over Twin Lens Reflex, but the need to differentiate lives on.

 

The reduction in battery peak power indicates to me that maybe the 'gear ratio' of the PSD was changed (fist time) to give less than 28% of ICE torque to MG1, giving more to the mechanical path.
This way, the electrical path will have less losses both by the more efficient components as well as by the lower current through them.
In this configuration battery peak power and MG2 rated power can both be lower.

 

that makes sense and would explain drop in ICE power output: they prioritized low end torque to compensate for it. In ICE realm improving low end usually means loss of the top, it is a trade off.

 

Does anyone know what were the HSD losses in Gen3? Is it 20% of 5% or is it 20% of 20%?

 

The expected improvement in fuel economy which now seems to be 15 to 23% (depending on model and test cycle) is comprised of many small improvements in many areas. There is no other way to improve the current best.
To me, the complete picture is of much more interest than trying to figure out how much each small improvement contributes.

 

Well Mazda is talking about 30% improvement with SkyActiv2. How? Switching to HCCI and 1:18 CR. I agree with you unless you go to radically different technology improvements are incremental at best.

 

The Gen2, Gen3 and some other vehicles have Pagoda roof.

The Gen4 Staff Manual says nothing about the roof.

Ken@Japan

 

i wonder if that will allow for aftermarket sunroof.

 

Thank God for that...

 

I think they call it pagoda for those indentation lines.. maybe it is not such a big deal anymore

 

Oh, I think I get it: when the sun roof opens it lifts up? There was discussion too, on the "what drives us" debrief show after Vegas reveal: the sun roof on 2016 no longer does this.