Best type of gas for Prime?

Hey that's my speech, sort of. Well refining is continuous processes but product blending is batches/tanks.
Yes gaso quality can vary because energy content/MPG is not spec, so that can vary within limits.
Those of us in EPA RFG areas pretty much get steady diet without much difference in quality due to the EPA recipe.
The unique aspect is the additive/detergent package which is company specific. If I really want to know quality, I get a sample in a gaso can measure density and ethanol content. But there is not much point of that in my RFG area, although I checked.

Good, I am glad someone can get E0. My point though is that E0 is essentially banned is large swaths of the USA (CA/Northeast Corridor down to Va. Beach). So many of us (even those with PHEV) do not have the option to use E0.

That sounds reasonable. The main reason for water separation in E10 would probably be exposure to moisture from air. The modern gaso tanks are complex and probably keep the air out, so that's probably why longer times are OK. Different story on my lawnmower where there is more chance for moist air to get into the gaso can and gaso tank.

 

Asked and answered a MILLION TIMES ALREADY (almost literally).
Please do some searching.

The answer is: Whatever it calls for in your owners manual.
Spending more than is required is just stupid.

 

Find ethanol free gas stations at:

Ethanol-free gas stations in the U.S. and Canada

Also try to find a brand that is:

Licensed Brands | Top Tier Gas

 

Depending on one's state, ethanol-free may not be an option. In California, a low vapor pressure blend is sold in the summer, a somewhat cheaper blend in the winter. No choice. And since it is a special blend, it is obtainable only from California refineries, and there are regularly scheduled shortages (and associated price increases) due to refineries being down for routine maintenance.

Top-tier IS an option here.

 

As I recall, higher-octane gasolines run a bit hotter too, which doesn't help the energy-efficiency picture. In other words, it could even be bad for mileage and/or the cooling system over time.


iPhone ? Pro

 

ONLY when it is used in a high compression, high performance engines.
OCTANE is a measure of a fuels resistance to pre-detonation due to heat and pressure (dieseling).
A lot of other characteristics are often associated with the octane number.......NONE of which is true based on that number alone.

 

Sure is hard to refute tired old myths. Increased carbon when using high octane is another myth that is hard to kill. Buy 87 AKI (antiknock index) as labeled in the U.S. and Canada. Other countries use other rating systems with different numbers.* Or spend more, buy higher AKI, feel like you're doing something special for your car. The only harm is to your wallet.


*There are two methods of testing the antiknock ability of gasoline, the Research Octane Number (RON) and the Motor Octane Number (MON). In the U.S. and Canada the posted Anti Knock Index (AKI) is the numerical average of the RON and the MON. This number will be lower than just the RON used in other countries.

 

This guy knows his stuff!!

.

 

Real Gasoline, not Ethanol | Page 2 | PriusChat
Non Ethanol Gasoline | PriusChat

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About 10 years ago, Huntsville still was pretty much free of E10 so I conducted a series of fuel studies. This involved running our 2003 Prius out of gas about 30 times to refuel with gasoline from brand suppliers both regular but also premium. I measure the car performance doing a maximum power, hill climb up a 525 ft (160 m), 8% grade hill. The results:

1. There were differences in energy content of regular gas between the brands, Shell and Exxon were higher energy than the other brands.
2. All high octanes had the same energy content as the lower energy, regular.
3. The 1.5L Prius did 'tune' the spark advance and slightly increase the efficiency at maximum power . . . not enough to compensate for the higher cost.

Sad to say, E10 has become "universal" and the few pure gas vendors are not worth study. Their prices are too high to be a practical alternative.

I also did an E10 to E85 test. The results:

1. Prius won't throw a code at E50 but anything above does light the check engine light. The code indicates it ran out of spark advance.
2. The price of higher than E10 is not proportional to the loss of energy. Yet curiously there is a disconnect between the retail and wholesale price of ethanol gasolines. If there were 'fair' retail pricing proportional to the wholesale prices, high ethanol fuel would have a slight cost advantage per mile.
3. High ethanol fuel showed the same spark advance efficiency in the hill climb test as premium fuel. But the cost of high ethanol fuel was not a practical option compared to E10.

Bob Wilson

 

I copy pasted this from the 'real gasoline, not ethanol' thread:

• Pure hydrocarbon E0 (0% ethanol) gasoline only holds 150 ppm dissolved water
• E10 (10% ethanol) gas can hold up 6000-7000 ppm dissolved water (that's 0.6 to 0.7 wt%)

So the take away to me is that Ethanol free gas is generally recommended for small engines because the shelf life is longer. Ethanol contains more water, and water is bad inside our gas tank.

Personally I will now use Ethanol free gas especially for Plug-in Prime because we could go months running on EV mode only and letting the same tank of gas sit for a long time.

There's a endless debate on Premium fuel vs regular fuel or which gas brand have the best additives. But one thing I am convinced is to feed pure gasoline into my Prime not government subsidized corn.

Petroleum = Non-renewable resource

 

Ethanol may contain more water. If you indeed go months without refreshing the gasoline in your tank, do use a stabilizer suitable for ethanol gasoline. If one uses up their gasoline somewhat regularly and buys from a station with a good turnover, don't worry about ethanol in gasoline.

 

The only issue with 6 to 12 month old gas I can foresee is using a gas that has the wrong vapor pressure for your current weather/temperature conditions. But I can't think of a single post where any Prius type wouldn't start do to this.

 

I'm thinking, once my P.Prime arrives (about 2 weeks! Hoorah!) I'll shoot for going to the gas station about once a month, rather than about once a week, to keep the gas from getting too stale.

I'll "throttle" (haha) that by adjusting the amount of gas I pump. We'll see, but I'm guessing I'll need to burn a couple gallons per month under normal, non-EV usage. So perhaps plan on buying 2-3 gallons once per month...

A colleague who drives a Gen-1 Chevy Volt said that it keeps track of how old the gas is, and forces it to burn that gas if it gets too old. Do any of you know whether the P.Prime does that?

Anybody know where one can get gasoline stabilizer in substantial, car-appropriate quantities? I've seen it in very small quantities in lawn-mower shops, but not in large quantities.


iPhone ? Pro

 

Your conclusion is off just a little bit.
Ethanol CAN contain more water.
That doesn't mean that it DOES necessarily in any given circumstance.

 

Yes pretty sure it does and "age burn" similar to the Volt.

Larger bottles of stabilizer can be had at any auto parts store and even WalMart.

I think you would be better off waiting until the tank is half empty to fill up rather than putting in a splash each week.

Using a stabilizer is good but don't do that TOO often. Having too much in there can cause it to run rough.

 

So, again, my current best-guess for gasoline purchases is probably be buying 2-3 gallons about once per month, and yes, refilling when empty.

Thanks, regarding stabilizer; until now I hadn't had any need to look for it, other than in very-small quantities for lawn&garden equipment.


iPhone ? Pro

 

I'm with you! Also, as pointed out by Mr. Tracy, our gas tanks are pretty well sealed; remember, our 50-state Prii are smog controlled by EPA, and CARB rules not to give off vapors and this helps keep water out. I think if you go to a regular, high-volume gas station you should be ok. If you're that worried, stop charging your car for a while til the gas runs down and then fill 'er up! !
Toyota says up to a year; hey fill it every 2 months like I did; no sweat! I worry more about peasants who park too close and want to ding my beauty with their Lumber Wagons! Har, har!

.

 

I don't see how those two things fit together.
Unless maybe you mean that occasionally you will be taking LONG road trips.