Updated MPG vs MPH chart

[bwilson4web]

I've added three data points:

The 19, 25 and 40 mph points were at 91-95F. I also revalidated the 70 mph data point and got a very similar number. Looks like I need:

• 32-33 mph
• 45 mph
• 80 mph - repeat at summer temperatures w/o defroster
• 55 mph - "I can't drive 55!"

Bob Wilson

[SageBrush]

Now Bob, I understand that it was a little bit humid and warm, but please tell me you didn't open a window.

[bwilson4web]

It was dry enough and I had a 19, 25 and 40 mph breeze. Yes, the windows were down at least enough to get a nice breeze. <grins>

I grew up in Oklahoma in the days before car air conditioning and home cooling were fans and swamp coolers. In my Grandmother's case, a flour sack cloth stretched over the screen door occasionally doused with well water.





It has been my experience that if the vehicle sustains any given performance for 10 miles, the Prius can sustain it until the tank is empty.

The following is my first cell phone photo of the day showing the warm-up profile:



This warm-up profile has me scratching my head:

• EV mode - even during warm-up, the vehicle auto-stops the engine at lights. This is a very good thing!!!
• nine minutes - I've seen 5 and now 9 minutes to achieve warm-up system efficiency. This remains a puzzle.

Bob Wilson

[F8L]

Thanks Bob!

[FireEngineer]

Bob,

I think you need to check your highway between 55 and 70MPH more, I've been seeing numbers at least 5 MPG better than yours.

And I agree, the warm-up is not the greatest, almost the same as the Gen II. If you P&G real good you can keep the engine temp below 180F.

Wayne

[bwilson4web]

Originally Posted by FireEngineer

. . .
I think you need to check your highway between 55 and 70MPH more, I've been seeing numbers at least 5 MPG better than yours.

Those were 'off the dealer lot' numbers and conservative:

• tires not fully inflated
• Shell 89, E10 - testing Shell 87, E10 now but straight gas tank was much better

Originally Posted by FireEngineer

. . . And I agree, the warm-up is not the greatest, almost the same as the Gen II. . . .

Instrumentation is needed but I've got so much on my plate now.

Bob Wilson

[carz89]

Bob - were you using any particular driving techniques (like P&G) to get maximum mileage, or were you just driving like your typical driver?

[bwilson4web]

Originally Posted by carz89

Bob - were you using any particular driving techniques (like P&G) to get maximum mileage, or were you just driving like your typical driver?

I use cruise control to maintain the speed and try to find a relatively flat road, at least 10 miles. I then make two runs, one in each direction, and once I get to cruise speed, reset the trip meter.

So none of my numbers try to include the acceleration load but this makes sense if you are doing a cross country trip. The steady-state, cruise control speed should ... within the temperature limits ... be reproducible.

Bob Wilson

[VABeachPrius]

Bob,

Will you overlay the data for the 2006 prius with the the 2010 prius. I am interested to see if there is a gain in MPG for steady state speeds of around 20-25 mph.

I would have anticipated that the mpg for the 20 mph rage to be over 100. Were you limited to the gages in the car and not a scangage?

Deadphish in va beach was kind enough to give me my first look at a 2010. It will be some time before I upgrade. I have really sped up my travels, but I am still holding a lifetime average of 64.3 mph for 405xx miles.

I met the owner of Priority Toyota while talking to deadphish, I told him about my best tank and he wants a picture. He said he was going to forward it to toyota usa. We shall see.

Initially, I was a beliver of P&G, but have found it is just easier to drive slow and anticipate traffic with pumped up tires and no AC.

With the improvements in the gen 4 (technicality) i am sure my lifetime average would be in the 70's.

[bwilson4web]

Originally Posted by VABeachPrius

. . .
Will you overlay the data for the 2006 prius with the the 2010 prius. I am interested to see if there is a gain in MPG for steady state speeds of around 20-25 mph.

Overlay is hard because it means mixing spreadsheets to do it right or fiddling with scales. Let me put them together and then flip between them until I can take time to do it right:


The efficiency curve is for the 1.6L NHW11 and has all of the NHW20 low speed data points. I also have some high speed NHW20 data points in this chart:

Take care with some of the data that was captured in high temperatures.

Originally Posted by VABeachPrius

. . . I would have anticipated that the mpg for the 20 mph rage to be over 100. Were you limited to the gages in the car and not a scangage?

I have something else in mind. <grins>

Originally Posted by VABeachPrius

. . .With the improvements in the gen 4 (technicality) i am sure my lifetime average would be in the 70's.

I'm seeing a solid +5 MPG with the 2010 and that is with ordinary driving. I think a lot of us are still investigating this vehicle. <wink>

Bob Wilson