Featured Stock Toyota Prius Breaks MPG Record for Cross-Country Drive

Kudos to Wayne Gerdes of CleanMPG.

His fill-up technique makes me cringe though; he constantly fills the tank to the top of the neck, to avoid gas pump auto-shut-off vagaries I think.

Wonder how much difference the 19" wheels would have made.

 

Freek'n Wayne ... at it again

Skimmed the read & didn't note what his average speed was . One can only imagine he was averaging (from personal experience) under 40mpg ... a speed making the trip uncomfortably long ... both for time as well as lumbar-wise.
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5th Gen Toyota Prius Sets GUINNESS WORLD RECORD for Highest MPG from Coast-to-Coast | CleanMPG

His journal of the trip is in this thread.
Meet the US Spec, All-new, 5th Gen, 2023 Toyota Prius Hybrid | Page 8 | CleanMPG

 

Wayne's slow speed stunt begs (another) the question .... and Wayne might be the best person to figure it out.
If you hypermile a model 3, it too - will get ridiculously high range/efficiency driving ridiculously careful over 3,000 miles.
Record for a model 3 single charge is over 600 miles.
That 3,200 mile total drive would thus represent 5⅓ recharges ... or ~302kWh
For rounding - say 1gal if gas is equivalent to 30kwh's ....
11 gallons equivalent ?
The gen5 pri's 93mpg times 11 gallons .... that'd be just 1,023 miles ... only enough gas to get ⅓ of the way across the USA

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He did one with a Taycan for shortest charge time on the trip.

 

Hmm, doing cross-country at a 25-mph cruising speed without the A/C on in the summertime. I guess that is OK if you make money from it.

I get 120 mpg (real, adjusted for any SOC drop and meter overestimation) round-trip in long stop-and-go freeway driving in my 2021 Prius Prime Limited.

Gen 6 should get far better fuel economy with its currently being-developed lean-burn engine.

 

Isn't this more or less the ideal time of year to try a stunt like this? Probably won't need much heat or A/C in many locations.

We always get our car's best MPG about this time of year.

 

Shoot, that is nothin' as last year, I drove +4,000 miles Huntsville, Las Vegas, Los Angeles, Tucson, Vicksburg, and home without burning one drop of gas.

Bob Wilson

 

But with burning coal instead, like in the old times.

 

That would mean driving 23.36hr shifts each day. 40mph is 15hr ones.

 

You can probably easily get around 90 mpg in a Gen 4/Gen 5 Prius/Prius Prime (excluding the 19" wheels) if you cruise at 40 mph without A/C and with a cold start only once a day.

Gen 4 and Gen 5 are very similar cars. Gen 6 will be a lot different. Even without hypermiling you could be able to get 90 mpg and with hypermiling around 150 mpg.

 

A horse makes gas as you travel on it. Eats plants for free along the way when no one is looking. Smarter than the smartest car, it can be your friend. Nothing to see here.

 

We'll have an idea when the new Corolla comes out.

 

Bronx Cheer to Wayne

Can't comment on the wheels question but the fill technique is not good for the environment or your pocketbook as overfilling to the fuel neck means you are filling the splash space or vapor space which is there for a reason.

Spaces within a gas tank and their use are defined by the SAE in a document called J398.

In my Rav 4 hybrid, the size of the fuel tank is 14.5 US gallons. The usable fuel space is 9.8 gallons described by a published Toyota C-SP which cautions against overfilling.

This way of measuring a fuel tank is the same as defined by the NIST. Both go into detail about when certain warnings come on and when F and E are to be indicated. Another document supporting this is published as NIST B-014 and dates back to August 2005.

Using the overfill technique can damage the purge valve and the charcoal canister. How these work can be summarized below:

The purge valve is a component connected to the charcoal canister in a vehicle's fuel system.

Its primary function is to control the flow of fuel vapors from the canister into the engine for combustion.

Here's how the purge valve works:

The engine control module (ECM) or powertrain control module (PCM) monitors various factors, such as engine load and coolant temperature, to determine when to open the purge valve.

When certain conditions are met, such as the engine reaching a specific operating temperature, the ECM/PCM sends a signal to the purge valve to open.

With the purge valve open, fresh air is drawn into the charcoal canister, creating a purge flow.

The purge flow pulls the stored fuel vapors from the charcoal bed in the canister through the open purge valve and into the engine intake manifold.

Once in the engine intake manifold, the fuel vapors mix with the incoming air and are burned during the combustion process.

By directing the fuel vapors into the engine for combustion, the purge valve helps reduce emissions and prevents the release of harmful pollutants into the atmosphere.

It's important to note that the specific timing and duration of the purge valve operation are controlled by the ECM/PCM, which takes into account various factors to optimize engine performance and emissions control.

Oh and it also should be noted that you will pay if these are damaged as Toyota considers it abuse.

NIST = National Institute of Standards
SAE = Society of Automotive Engineers

 

I'm not aware of any thermal engine that can anywhere near 30 kWh of mechanical energy out of a gallon of gasoline. Though some combined-cycle thermal electric plants can get a bit over 20 kWh out a gallon-equivalent of natural gas.

 

I'd like more detail on those technical specs, but don't want to pay $83 just to see SAE J398. Haven't yet found links to the NIST item.

A RAV4 Hybrid has only 9.8 "usable" gallons? 4.2 gallons less than "advertised"?

I thought my RAV4 Prime has the same tank, yet have run well past that several times without any low fuel indications. The most so far was 11.2 gallons to the first nozzle cut-out click, with DTE showing 14 miles left, but no low fuel warning light yet. And the Owner's Manual indicates about 2.3 gallons should be left when the low fuel warning does light up.

I ran my Prius to less than one gallon below its advertised tank capacity, and didn't run dry, though it was well past the low fuel warning. I ran my Subaru completely out -- by extreme luck, right at a fuel pump moments after wimping out on an intentional attempt -- and the refill was a few hundredths of a gallon greater than the advertised capacity. Round to the nearest tenth, it was right on.

 

And I thought it was all those windmills by the highway or the distantly glowing nukie plants:


Ironic, the Navaho Nation shutdown their big coal plant around that time. I was hoping to see high plains smog but it was obscured by the diesel trucks and trains.

Bob Wilson

 

The 9.8 gallons sounds like something Toyota put out when people started having issues with filling their Rav4.

 

Ha !!
Just fact checked my #5 post;

Electric vs. Gas Cars: Is It Cheaper to Drive an EV?.

so - it wouldn't be too unfair to say that the model 3 doing a low-speed stunt like the OP could achieve an easy 270mpg equivalence. But that painfully slow & low speed trip? No thanks
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