2010 Prius 2ZR-FXE engine efficiency map

At 4000 RPM a Prius must be moving along
the highway like a crazed demon from hell.

 

this is europe.

my 88hp nissan moved at 100mph with no problems for 600 miles the other day

 

Hi Tom

Actually it does make a lot of sense. I'm capturing OBDII data and this is the plot you asked for. It seems that there is a different path (in light-blue) for revving when the coolant temperature is below 70ºC (158ºF)

Big hugs from Frank



[Click here for zoom]

 

That's what got me interested in the car in the first place: I saw a 2010 model accelerating at a speed I didn't think a hybrid could do. I wouldn't call my 2011 a highway demon, but I have caught myself going at speeds way above what I intended without realising.

I found I can enact some fun by putting the car both in power and the gear selector in B (to keep the ICE running) then it's possible make very quick progress when there is little traffic in the way. I wish I'd owned this car back in Australia.

 

Ken,

Is there any chance you could re-publish your 2ZR-FXE engine efficiency chart?
When PriusChat moved to its new format, the links to many old charts were lost!

 

From EcoModder -- IIRC this is the same figure Ken posted
File:Toyota 2zrfxe 1.8l prius bsfc1.jpg - EcoModder

 

Is there anyone with a OBD reader that can provide an estimate of power loss when in high speed no-load (just about 1000rpm) of the engine?
For 2 Gen Prius I have a friend that gave me 1kw as rough value (diff between 68km/h and 70km/h energy flow to batt)...
Thank you in advance

 

Hobbit has said 2 kw to turn the ICE, unrelated to fuel combustion.
Incidentally, it is this factor that provides most of the benefit of P&G: ~ 2/3rds of the time the driver is saving 2 kw.

It is also why hybrids that can glide at high(er) speeds have quite an advantage in a hypermiler's hands if the route lets them stay below the spinning_ICE threshold.

 

...would that be 41 mph? The cross-over point where the ICE engine begins spinning the sun gear?

 

It varies by Prius generation, and whether the threshold is reached from a lower or higher value.

For your car, ~ 45 from below, ~ 43 from above.

 

Although true when comparing between Gen2 and Gen3 because they have the same power split ratio, it is not true with Ford Hybrids that can go up to 85 mph with ICE off.

The compromise to allow 85 mph ICE off operation is to increase torque split to MG1. This in effect reduces torque split to the wheels (direct mechanical drive).

Prius ICE splits 72% of the torque to the wheels while 28% splits to MG1 (generator). Ford hybrids split less to wheels and more to generator.

That adds conversion loss because more power end up inn MG2 (traction motor) rather than ICE turning the wheels directly.

Although 85 mph glide has advantage, inefficiency introduced in the acceleration should negate it. Plus, you'll lose speed fast due to high wind resistance at those speed.

 

I pretty much agree with all your points. I was thinking of 50 mph Vs 40, or hilly routes.

 

Q: I found the Mg1/ICE/MG2 equations & ratio-constants (applicable to Gen I & II PSD), but what are they NOW with the changed Gen III ratios & splits?

 

That is 22 mph and 28 mph.

Dan, 3rd gen from the sun