CleanMPG World Fuel Economy Championships - Records smashed!

[ItsNotAboutTheMoney]

Welcome to CleanMPG, Lee.

To start, read the CleanMPG Primer, which will take you through introductory articles.

Then you can introduce yourself in the Welcome To CleanMPG thread, or start a new thread in Start Your Journey Here if you have any questions. Tell us about yourself: the vehicles you drive, the area where you live, your driving patterns (how many miles, what the traffic's like, stop-and-go/interstate etc) and, of course, your current mileage and any fuel-saving techniques you're already using. We won't press, but feel free to add any background information about yourself. We're a community of people.

There are also vehicle-specific sub-forums where you can ask specific information or share the knowledge that you gain. Posting in those sub-forums will get the attention of other owners of the same or similar vehicles.

It helps us help you if you edit your profile and add details of your vehicle(s) (Year, Make, Model, engine size and transmission) and your location (a region will do) so that it will appear in the right-hand side of your post headers (as the Prius, Civic and Maine appear in mine). Techniques depend so much on the car, traffic, terrain and climate so it will save additional posts asking and providing information.

[waltermlee]

When the tire pressure is set at 80 psi - did you limit the top speed to 20 mph for safety reasons or do you believe that the tires could go at a higher top speed? That is - was the 80 psi setting for the Championship driving environment only?

How did you get the Prius SoC up to 70%?
Was that for just the first driver or was the SoC reset to 70% for each driver?

[xcel]

Hi Walter:

Burst pressure on today’s tires are many multiples of max sidewall so you do not have a safety concern here.

Everyone took off with an initial 70% SoC in the Prius’ with both initial and final SoC recorded in order to balance the results. You can force charge a Prius to 70 + %.

Wayne

[diamondlarry]

Originally Posted by xcel

Hi Walter:

Burst pressure on today’s tires are many multiples of max sidewall so you do not have a safety concern here.

Everyone took off with an initial 70% SoC in the Prius’ with both initial and final SoC recorded in order to balance the results. You can force charge a Prius to 70 + %.

Wayne

Yes Walter, I hear a Prius can be force charged to about 83%. I have had multiple 10's of thousands of miles both local and highway at 80 psi (occasionally higher) with no safety issues and no uneven wear.

[waltermlee]

Originally Posted by xcel

Hi Walter:

Burst pressure on today’s tires are many multiples of max sidewall so you do not have a safety concern here.

Everyone took off with an initial 70% SoC in the Prius’ with both initial and final SoC recorded in order to balance the results. You can force charge a Prius to 70 + %.

Wayne

Thanks for your quick response. I'm a scary cat so I have
been only gradually upping my tire pressure ( I'm currently
testing out 50psi/48psi). My concern is not that the tire air
seals will fail but that road handling/braking performance
might degrade or change in such a way that I am unable
to compensate for it. I am using stock Yokohama Avid
S33 ( max sidewall is 44 psi).

I read that Toyota engineers forced the SOC up by
stopping from a very high speed. Is that how you forced
a charge on the Prius or did you use a battery charger?
Thanks

Walter Lee
2010 Toyota Prius III, oem floormats
Ribbon Blue/Dk Grey
ScangaugeII (AVG/MPG, Fwt, SoC, GPH)
Yokohama Avid S33 (50/48)
odeometer +13000 miles/59 mpg overall
MD/DC/VA metro area

[waltermlee]

Originally Posted by diamondlarry

Yes Walter, I hear a Prius can be force charged to about 83%. I have had multiple 10's of thousands of miles both local and highway at 80 psi (occasionally higher) with no safety issues and no uneven wear.

Wowsers!

Thanks. As a hypermiler neophyte - the safety issues is my
own driving skills and whether I respond correctly to a given
driving condition which is why I am only slowly upping my
tire pressure so that I can get a feel of any difference in
handling. I am using Yokohama Avid S33 on a 2010 Prius 3.

Last December, I had upped my tire pressure
to 50/48 psi. While it was raining on a downhill section of
a curved crowned asphalt road (Nicholson Ln, North
Bethesda,MD) an SUV merged in front of me and
shortly afterwards stopped to make a left turn. While I
had more than enough distance to stop on the wet
downhill - the Prius shook/vibrated briefly as I braked
hard from 35mph to 0mph. I had stopped about 20 feet
behind the SUV so I had enough distance behind me
but the vibration suggested that the ABS was operating
because I had lost some traction. After that incident,
I dropped my tire pressure to 44/42 psi. With drier
weather, I have upped my tire pressure back up to 50/48
with a keener focus on having a longer stopping distance
when driving on wet roads.

[diamondlarry]

To answer your question about how the Prius' were force charged, it is done by putting it in D then, while holding the brake pedal down, you press on the gas. A couple of years ago, I ran an experiment with my Prius where I left home with some recycling stuff and when I got there(approx 7 miles away), I forced charged to the full capacity. On the way back, I had 255 mpg showing on the Scanguage. When figuring in the fuel used while charging, it came to 103 mpg for the round trip. For me, this was almost a wash since that is about what I could usually do.

[waltermlee]

Originally Posted by diamondlarry

To answer your question about how the Prius' were force charged, it is done by putting it in D then, while holding the brake pedal down, you press on the gas. A couple of years ago, I ran an experiment with my Prius where I left home with some recycling stuff and when I got there(approx 7 miles away), I forced charged to the full capacity. On the way back, I had 255 mpg showing on the Scanguage. When figuring in the fuel used while charging, it came to 103 mpg for the round trip. For me, this was almost a wash since that is about what I could usually do.

Wowser! What a neat Trick!

[Harold]

Run that by me again! Force charge a Prius by applying the brake and hold the throttle down? Are you at a stand still when you do this and how much gas do you give it?? H

[PaleMelanesian]

Don't bother. It didn't actually save any gas. It only gives a huge number if you ignore the gas used to force a high SOC.

Originally Posted by diamondlarry

When figuring in the fuel used while charging, it came to 103 mpg for the round trip. For me, this was almost a wash since that is about what I could usually do.