recommended grade of gasoline

MNSteve said:
Agreed. Amazing the things you learn here that have nothing to do with the Clarity.

I did a little research when this thread appeared and found two flavors of information on the topic (ethanol in gas). It's either the greatest thing ever, or evil incarnate!
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And that's without even mentioning the paradox of why it is that we use petroleum to make fertilizer to grow corn to make back into fuel...
 
craze1cars said:
The specific words Honda actually uses is that you should use TOP TIER DETERGENT GASOLINE. This may be what the dealership said to O.P., and was lost in translation. Top Tier is a branding thing which has absolutely nothing to do with octane, or ethanol. Truth is Honda specifically states there is no sense in using higher octane than the manual calls for. They also recommend you should purchase your gasoline only from retailers on this list:
https://www.toptiergas.com/licensed-brands/
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Thank you for this useful information. I had seen the "top tier" logo and etc. at our local Costco, but had dismissed it as useless pure marketing noise. (At least Costco's gas stations are on the list to which you linked ... in our area, their price per gallon is substantially below most competitors most of the time.)
 
KentuckyKen said:
After all these informative posts, I now confess total ignorance on the ethanol issue with the one exception that I can boldly say I prefer my ethanol in my glass and not in my tank.
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Though I get your joke about drinking alcohol I feel the need to point out ethanol is poisonous. You should stick to your local bourbon.
 
David Towle said:
No, ethanol is not less efficient. That has nothing to do with it. Ethanol has a lower heat of combustion than gasoline.
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Fair enough...I used the wrong word...again.

Net result that matters from a user and/or tuner perspective, in layman’s terms, is that ethanol produces 33% less power than gasoline, for the same volume. Meaning if you want to run an ethanol fueled vehicle the same distance, or at the same HP level, as a gasoline vehicle would run on a gallon of gasoline, you’d need to pump about 1.33 gallons thru the system in the same amount of time. With e10 you’d need to pump about 1.03 gallons. E15 you’d need about 1.05 gallons.

The ENGINE becomes less efficient, not the fuel. Running e10 worsens fuel economy by approximately 3% when compared to non-ethanol fuel.

And before someone says buying premium guarantees ethanol free fuel, this varies by state. Most states have ethanol in all octane grades. A select few prohibit it in premium. Ethanol is an octane booster. Because of this, in the majority of states that allow ethanol in premium, many of the 93 fuels have a HIGHER concentration of ethanol than the 87 octane in the next pump does. After all E85 is 105 to 108 octane usually, which is why the racing community loves the stuff...it can run much higher compression ratios without detonation. But For those buying premium at the pump in an effort to avoid ethanol, chew on that fact for a while...you MIGHT be buying MORE ethanol than if you just stayed with 87. While this is not true everywhere, it is in MANY places.

Also lower octane fuel is more volatile, it burns hotter than higher octane fuel. For this reason many vehicles get better fuel mileage and hp out of 87 than 93...but usually only those with open loop fixed fuel/ignition map systems (this is true for my fixed map fuel injected snowmobiles....87 is more powerful than 93 in them as proven in repeated speed tests, whether ethanol free or not). But most modern cars are closed loop and actively adjust fuel mixture and ignition on the fly based on combustion efficiency taking place, making the variable volatility between the fuels mostly irrelevant...

And now we get yet deeper into the weeds. I just love a good fuel topic. Let’s start an oil topic!
 
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Just thought this might be an appropriate place to put this, since I stumbled across it. Maybe it's been here before I don't know. But I find it to be educational. Clarity is not mentioned, but with fuel things coming up here recently I figure it should be known that Clarity has nearly the same style of long-term fuel storage and preservation systems engineered into it, for the same reasons, as the Volt discussed here has...biggest difference being that Chevy puts all the info on the screen for owners to see, while Honda for unknown reasons does not and leaves its owners largely in the dark about what it's doing and how it works...:
http://bestride.com/news/technology...-to-keep-your-fuel-fresh-heres-how-they-do-it
 
Wow this chat room has all the information I look for. I wanted to know if 87 was aok or if I needed to pay for higher grade. Some one told me new cars run better on leener gas. I always put 87 in the tank and have no problem. Thanks for the info and Happy New Years to youall.

Edd
 
craze1cars said:
Fair enough...I used the wrong word...again.

Net result that matters from a user and/or tuner perspective, in layman’s terms, is that ethanol produces 33% less power than gasoline, for the same volume. Meaning if you want to run an ethanol fueled vehicle the same distance, or at the same HP level, as a gasoline vehicle would run on a gallon of gasoline, you’d need to pump about 1.33 gallons thru the system in the same amount of time. With e10 you’d need to pump about 1.03 gallons. E15 you’d need about 1.05 gallons.

The ENGINE becomes less efficient, not the fuel. Running e10 worsens fuel economy by approximately 3% when compared to non-ethanol fuel.

And before someone says buying premium guarantees ethanol free fuel, this varies by state. Most states have ethanol in all octane grades. A select few prohibit it in premium. Ethanol is an octane booster. Because of this, in the majority of states that allow ethanol in premium, many of the 93 fuels have a HIGHER concentration of ethanol than the 87 octane in the next pump does. After all E85 is 105 to 108 octane usually, which is why the racing community loves the stuff...it can run much higher compression ratios without detonation. But For those buying premium at the pump in an effort to avoid ethanol, chew on that fact for a while...you MIGHT be buying MORE ethanol than if you just stayed with 87. While this is not true everywhere, it is in MANY places.

Also lower octane fuel is more volatile, it burns hotter than higher octane fuel. For this reason many vehicles get better fuel mileage and hp out of 87 than 93...but usually only those with open loop fixed fuel/ignition map systems (this is true for my fixed map fuel injected snowmobiles....87 is more powerful than 93 in them as proven in repeated speed tests, whether ethanol free or not). But most modern cars are closed loop and actively adjust fuel mixture and ignition on the fly based on combustion efficiency taking place, making the variable volatility between the fuels mostly irrelevant...

And now we get yet deeper into the weeds. I just love a good fuel topic. Let’s start an oil topic!
Click to expand...

Agree with all that, and I’ll add a couple more opinions (having rejetted and cleaned MANY carbs myself):

-ethanol fuel leaves behind more deposits and is “dirtier” IMHO, especially at lower octanes (Carbon deposits mostly).

-aviation fuels are also ethanol free for the reasons you stated many posts ago.

Yamaha Ring Free is one of the best carbon cleaner additives available, IMHO. I don’t know if BG has anything similar.

-Skip


Sent from my iPhone using Tapatalk
 
Thanks @craze1cars. That’s a very informative site and article by Mr Goreham.
It’s common knowledge among the Volt community that their algorithm is set to not allow gas to stay in the tank past one year. However, the verdict is still out on whether the Clarity is set up the same way.
While it does perform periodic System Checks, we do not know if it is scheduling them with sufficient frequency and duration to burn at least 7 gal per year. The manual only says it will keep the engine on until it reaches operating temperature. In contrast, GM clearly tells its owners that the Bolt will burn at least one tank per year.
Posts seem to indicate that ours will not since there are no reports of System Checks/ICE operation more often than a month or so. My experience is that unintended or uncalled for ICE operation is a rare event on the order of every few months or so (with the exception of the known no regen allowed after full charge scenario where hard braking or large regen will cause it). And in my Clarity it only lasts for 5 min or so. So for me at 11 months, the algorithm is not going to burn off a tank in one year. I drive almost all EV and have taken only 2 trips in HV wirh ibly 12.6 hours on the ICE. It’s been six months since the last HV trip and fill up and I’ve not lost a bar on the gas gauge and the ICE has only come on 3 times for a few minutes each. Only one is those appeared to be a System Check; the other 2 were the no regen allowed after full charge events.

So even though we have a pressurized fuel system that helps keep the more volatile components of gas from evaporating, I am going to avoid ethanol gas and use Stabil until I start doing more HV or we have proof the Clarity acts like the Volt and burns gas before it gets older than 1 year. (And I’m not comfortable with even that level of retaining old gas in the tank)
I’d rather be cautious than sorry later.
But I admit it’s a moot point for most of us that unlike the minority, do drive enough in HV to be fueling every month or two and so don’t have to worry about this.

I currently have a full tank that’s been there for 6 months with <20 minutes of engine operation at idle like speeds and no loss of gas gauge bars. So in my case, it makes sense to me to use some Stabil. It can’t hurt and potentially can help prevent deposits. The trouble is that I can’t know if it did any good until it’s too late to matter. So, better safe than sorry for me.
YMMV
Edited to correct Bolt to Volt. However as @Robert_Alabama pointed out to me, the Bolt won’t burn a tank of gas in a year either! LOL
 
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KentuckyKen said:
Thanks @craze1cars.
I currently have a full tank that’s been there for 6 months with <20 minutes of engine operation at idle like speeds and no loss of gas gauge bars. So in my case, it makes sense to me to use some Stabil. It can’t hurt and potentially can help prevent deposits. The trouble is that I can’t know if it did any good until it’s too late to matter. So, better safe than sorry for me.
YMMV
Edited to correct Bolt to Volt. However as @Robert_Alabama pointed out to me, the Bolt won’t burn a tank of gas in a year either! LOL
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Has anyone ever seen any real information that Stabil actually works? All I've ever seen is propaganda from the company and those that sell it.
 
David Towle said:
Has anyone ever seen any real information that Stabil actually works? All I've ever seen is propaganda from the company and those that sell it.
Click to expand...
Haven’t seen any reputable third party tests but from the MSD (petroleum distallates), it appears it’s at least replacing the higher volatile hydrocarbons that evaporate first. Anybody know if it’s doing anything else?
Other than Stabil’s claims of proprietary ingredients that protect against gum and varnish build up?
All I can find are internet (non testing lab) articles claiming fuel stabilizers work by preventing oxidation of the long alkyl chains into fatty acid esters. And of course you can believe everything on the Internet!
It has however been around for 50 years so it must be doing something positive.
 
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I do the other way around. Use cheap gas from coscto and burn them periodically.
I try to maintain 1000mi/tank, which means about every two months.

The engine needs a spin anyway. Don't let the great 0w20 oil sleep in the bottom.

BTW, trip A (and the stats) can auto reset on each fill up.
 
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