Stupid Prius Tricks: Obtaining High Speed + High MPG in a hatchback

It's easy to obtain high mileage by driving slow, but can you obtain high mileage when driving 65 mph or faster for a distance of at least 100 miles?
Here is Team Virginia's first attempt at obtaining high speed, high mileage result in a Gen 3 hatchback:
We managed 65 mpg at a speed of 65 mph for a distance of just over 100 miles.
The goal is to set a better benchmark by exceeding either the 65 mpg or the 65 mph over a 100-mile stretch of driving a regular hatchback while still maintaining the other criterion: (e.g. 70 mpg at 65 mph, or 65 mpg at 70 mph...you get the idea.) But you have to drive safe and legally, and then post the HSI display and tell the rest of us how you managed to do that!

(We had 40 psi tires, 7,000 ft. altitude, tailwinds, cooperative trucks, and non-reformulated and non-ethanol gas.)

 

(^^^ answers to questions in the parentheses above)

I am sure that you all can do better than this benchmark because I was burdened by two handicaps:

1. It was over 90 degrees Fahrenheit and we were running the AC to help keep us and the HV battery cool.

2. I had a 100-pound DW in the passenger's seat and a half-ton of camping equipment in the rear, or was it a half-ton DW in the passenger's seat and 100 pounds of camping equipment in the rear?? In any case, unnecessary weight.

Cheers, mate!

 

Round trip??? 9,000 more miles??? I'm not driving back around the "Top Of The World" Highway in the Yukon for anybody!! Nope , nosirree Bob, noway, nohow! Already lost one tire coming this way and don't want to lose any more!

Which reminds me, final handicap I had was only 3LRR tires on the car right now, the right rear is a replacement Cooper tire of some sort .

Cheers!

 

Well I just found an interesting result and wasn't expecting the Spanish Inquisition!
<<Three caped men in outlandish garb with swords now leap out of the closet>>
NO ONE EXPECTS THE SPANISH INQUISITION !!!
(Apologies to Monty Python!)

Now I know how John Colter felt when he reported what he saw in Yellowstone.

Believe or discount the data point as you wish--the photo could, after all, be a clever Photoshop forgery or I could have hacked the car's computer to produce the display.

But Wikipedia lists the altitude of the Rock Springs starting point as 6388 feet and the altitude of the Rawlins finishing point as 6834 feet, so there was a net gain of about 446 feet during the 100 mile drive. Thus, altitude loss would not seem to be a creditable explanation of the observed result.

I am a pilot and profoundly aware of the effects of both tailwinds and altitude on the observed "gas mileage" of small aircraft during cross-country flights. I was simply experimenting with whether I could duplicate some of those effects in the Prius under the moderately high altitude terrain and moderate tailwinds I found myself in at the time.

 

Certainly wind is a BIG factor for mpg in my experience. A strong, direct tailwind bumps my mpg up noticeably. Headwinds knock it down of course, in exactly the same fashion as driving that much faster--worst mpg in my case recorded crossing the western plains of Canada against strong headwinds. But surprisingly the crosswind effect is also quite bad--I speculate that occurs because the crosswinds interfere with the flow of air around the vehicle and thus produce much more parasitic drag than you would expect.

 

I found E0 (not sure if RFG) at a gas station in Lake Geneva, WI, and filled up for a dash back to NoVa along the turnpikes. Got to just over 600 miles on that tank just East of Pittsburg after driving with blinking pip for 75 miles--DW was none too happy about that but we joined the 600-mile club. She is not keen to attempt the 700 or 800 mile clubs!
This thread's 65-65 trick was in southern Wyoming where the average altitude is near 7000 feet and the grades are surprisingly gentle.
We have explored using the Colonial Parkway at 26-35 mph in a nonstop loop where you turn around at Jamestown on one end and Yorktown on the other--it is easy to exceed 60 mpg at those speeds on that fairly level parkway, but I do not have the patience to do it for 20 or more hours!
The non RFG (thanks for that RFG map link!) E0 gas in Yukon, Alaska, Idaho, and Wyoming did seem to result in better mpg, but those data from our journey are confounded with the prevailing winds as we do each day's drive. Still, that fuel would absolutely be my choice for attempting high mpg results.

 

Other than the mushy brakes, did you have fun doing that?
I have fun exploring the car's capabilities under different situations.

 

Epic? Not sure but we did drive to Alaska and back: We departed July 1st and returned August 21st, so it was about a 7-week trek--we are still emptying car of all camping gear, vacuuming, washing bugs off, etc.
Our route was Fairfax --> Chicago --> Duluth --> Winnipeg --> Dawson Creek --> Whitehorse --> Fairbanks --> Anchorage --> Seward --> Tok --> Top Of The World Highway --> Dawson City --> Whitehorse --> Cassiar Highway --> Prince George --> Hope --> Seattle --> Olympic Peninsula --> Portland --> Boise --> Rawlins --> Kearney --> Iowa City --> Toledo --> Fairfax. Total distance was about 11,000 miles with average mpg of 54 or so (will calculate that after final fill up.). We used the "Prius Super RV" set up to camp, but stayed in motels and with relatives about 50% of time:
Fantastic natural scenery, lots of wildlife, interesting native and settler cultures, friendly people everywhere, so HIGHLY recommend trip.
To be fair, we also experienced rather rough roads (blew a tire, cracked the windshield, and vibrated bolts out of the Prius), moderate mosquitoes (bad year for them, good year for us!), temps from the 40s to the 90s (layering suggested), and very expensive motels (camping suggested as it was very cheap!).
We will post pics and narrative from this journey on our wanderungs.com website in a month or two, but let me know if you want/need any particular information and I will try to help.
Cheers!