Prius Marathon Run

[Ray Moore]

dead band acceleration is when there is no energy flow to or from the battery. I think that if it is teetering on the edge and going back and forth between to and from the battery then you are doing great. very little flow to and from the battery is almost as good as none.

[krousdb]

I have learned a lot as a result of participating in the marathon.

The first thing that we could all agree on is that there seems to be no correct way to accellerate. The Prius is very forgiving as long as you keep acceleraton within the 15 - 50 MPG range. Maybe the range is even wider but we did not try anything outside. Rick used 15-20 for his 115 MPG shift, I used 25-35 for my 115 MPG shift and Wayne used 40-50 for his 120MPG shift. The extra 5 MPG was more likely due to gliding down to much lower speeds than Rick or myself.

What I found best for my style was not deadband at all. It was what I call "accelerate with charge". I found that during the night the headlights made it difficult to maintain the HV battery charge so I had to revert to "accelerate with charge", pink arrows from ICE to wheels, green arrows from MG to battery, no orange arrows at all. This kept the battery level steady. I continued this technique on my second shift in the daytime and found that I had an abundance of charge (no headlights) and I could actually use stealth to help me over small hills instead of using the ICE. This is how I went from 105MPG to 112 MPG. So much for my deadband habit.

Another habit that I broke was to glide partially up a hill and then switch to ICE power to pulse the rest of the way up the hill. I switched to DWL (drive with load) in which I switched to ICE power as I approached the hill, held the gas pedal steady at 50-60MPG while I slowly bled off the speed, targeting 32MPH at the peak of the hill.

Combining those two changes, on my last shift, I was over 117 MPG before I decided it was time to end this marathon. Unfortunately I made that decision about 3 miles too early.

Dan

[dreichla]

[quote]
California Vehicle Code Section 21710:

But we can drive barefoot, right?

BTW....how can they see what gear I'm in?

Gee, I hope so!

What I found best for my style was not deadband at all. It was what I call "accelerate with charge". I found that during the night the headlights made it difficult to maintain the HV battery charge so I had to revert to "accelerate with charge", pink arrows from ICE to wheels, green arrows from MG to battery, no orange arrows at all. This kept the battery level steady. I continued this technique on my second shift in the daytime and found that I had an abundance of charge (no headlights) and I could actually use stealth to help me over small hills instead of using the ICE. This is how I went from 105MPG to 112 MPG. So much for my deadband habit.

I've started turning OFF my headlights during the day and have also noticed a slight change efficiency, although I see people pulling out in front of me more.

[Ray Moore]

Dan- I agree with everything you just said from my experience. The problem is that we have to compromise to keep other drivers happy so accelerate with charge is usually too slow.

I would really like to see you achieve 128 MPG so we can claim one mile per ounce of gas. This latest effort got one miler per 1.17 ounces of gas.

[krousdb]

Next stop, one mile per tablespoon!

[ltu1542hvy]

For whatever it's worth, theres a blurb about you guys over at autoblog

http://www.autoblog.com/entry/1234000147053641/

- Bill

[ehurtley]

Next stop, one mile per tablespoon!

That would be a bit extreme, as that would be 256 miles per gallon.

On a side note, I just registered (I've been over at PriusOnline for a while, and have read PriusChat for a while, but just registered,) and have to say one thing:

I went to college with the commander of the Space Shuttle (Eileen Collins,) and know her as an 'acquaintance'; yet I was more enrapt by this feat of eco-friendliness by total strangers than by the status of the shuttle landing!

[vincent1449p]

[quote]Final numbers: 1397 miles! 109.328 MPG! 12.78 gallons!</span>

That is awesome!!!

I 've also been following and I thought it might be easier to keep track with a spreadsheet. Please note that this is for reference only and I apologise if there were errors.

The effect of OAT and the no. of stops & slows on fuel economy can be clearly shown. However, I can't seem to corelate the percent ICE on against FE.

Vincent

[ken1784]

Hi Vincent,
Thank you for the nice spreadsheet.

However, I can't seem to corelate the percent ICE on against FE.

I don't understand what is the exact problem, but I'm going to try to solve...

There is an ICE-ON distance counter internally on SuperMID, but the distance is not displayed because of lack of display space.

For example, from the first Dan's data...
Fuel used: 4.501 L
ICE-ON FE: 12.41 km/L
ICE-ON distance: 4.501 X 12.41 = 55.86 km (hidden ICE-ON distance)
then
Percent ICE-ON: 55.86 / 200.38 = 0.279 or 27.9%

Is this calc clear for you?

Ken@Japan

[tochatihu]

Vincent, your spreadsheet is just as I was trying to develop, except you have kept in some of the seconday info I had skipped. Yours is better.

Do you approve if I post it on other Prius groups with credit to you?

DAS