2010 Prius 2ZR-FXE engine efficiency map

[ken1784]

Hello all,
One of Japanese Prius enthusiasts posted following charts on our community.
He agreed to post them here on PriusChat.

edit: the charts source: Toyota's article titled "Development of New 1.8-Liter Engine for Hybrid Vehicles" which was published at JSAE academic conference in May 2009.

The new 1.8L 2ZR-FXE engine is much more efficient than the previous 1.5L 1NZ-FXE engine.

Both engines trace most efficient area depending on power demand, and the 1.8L engine runs very efficient 220g/kWh area in the most useful medium rpm range.

Please note that the 1.8L engine's rpm number, for the 40kW output, is lower (3650rpm & within 230g/kWh area) than 1.5L's (4000rpm & out of 230g/kWh area).
I believe the vehicle cruising speed by 40kW is approx 95mph, and we can see the turning point at 3650rpm to get more torque than efficiency for higher speed.
It looks Toyota is trying to compete European diesels on 90mph cruising German autobahn.

Enjoy,
Ken@Japan

[DaveSheremata]

It's starting to boggle my mind a bit whenever I try to bounce the scalars around! (I'm probably not supposed to do that...

It looks a lot more efficient across the board - when you count out the circle to the 190g/kWh, the 2010 covers a lot more ground!

[FireEngineer]

Ken,

Thank you and the Japenese Prius community for sharing this with us. Though not as pretty as Bob Wilson's charts.

Wayne

[bwilson4web]

Originally Posted by FireEngineer

. . .
Thank you and the Japenese Prius communityfor sharing this with us. Though not as pretty as Bob Wilsons. . . .

I'm trying to get excel to 'do the right thing' and it is ugly what I have to do. But I am intrigued by 1NZ-FXE chart and what I measured in the field. Hobbit may have some insights to share but I'm finding anything over 2,600 rpm and we start to see a fall off and it is most evident from 3,200 and above. The crash at 4,150 and above is evident in both of our charts. It is the low rpm area that has me scratching my head.

I'll take the charts home and load them into excel to see if I can provide more rpm scale points. It is the low rpm side that has me curious.

Do our Japanese Prius friends with NHW20s and NHW11s try to keep their engine rpm in the region of the peak BSFC chart or lower than 2,600 rpm?

Thanks,
Bob Wilson

[jprates]

Bob, this seems to show that the improvement from the classic to 3G is well over 5% as you had reported at PTS isn't?

I hesitated to reply to your post back then, but I did thought it was too low of an improvement to be right.

On the other hand, one has to consider at which rpm we are talking about, and what load, don't we? Simply stating an x% value is too vague, or at least this is what I feel about it.

By what Ken as reported, we conclude that at least for 40kW generated output level the efficiency of the new engine is up by 9% compared to 2G.

Just out of curiosity, do you know what rpm would be needed to generate those same 40kW on the classic?

[bwilson4web]

Originally Posted by jprates

Bob, this seems to show that the improvement from the classic to 3G is well over 5% as you had reported at PTS isn't?

I hesitated to reply to your post back then, but I did thought it was too low of an improvement to be right.

The 2010 is also about 300 lbs, 136 kg., 10% heavier and I did not adjust for the different vehicle weights. I was trying to report the "net" improvement of the vehicle in a hill climb. The engine is superior.

Originally Posted by jprates

On the other hand, one has to consider at which rpm we are talking about, and what load, don't we? Simply stating an x% value is too vague, or at least this is what I feel about it.

By what Ken as reported, we conclude that at least for 40kW generated output level the efficiency of the new engine is up by 9% compared to 2G.

Just out of curiosity, do you know what rpm would be needed to generate those same 40kW on the classic?

It looks to be about 4,000 rpm in my NHW11.

Bob Wilson

[jprates]

Originally Posted by bwilson4web

The 2010 is also about 300 lbs, 136 kg., 10% heavier and I did not adjust for the different vehicle weights. I was trying to report the "net" improvement of the vehicle in a hill climb. The engine is superior.

Thanks for the clarification Bob.

[jprates]

Originally Posted by ken1784

Hello all,
One of Japanese Prius enthusiasts posted following charts on our community.
He agreed to post them here on PriusChat.

Ken, can I ask you the favor to ask your friend permission to post these same pics on my Portuguese speaking site Prius-PT.com?

[usbseawolf2000]

Wow, another thread to bookmark.

[efusco]

Originally Posted by usbseawolf2000

Wow, another thread to bookmark.

It was an instant sticky!