Does Premium Gasoline Have More Energy Than Regular?

[RDY4WAR]

Regular and premium will have the "same" energy potential (BTU/lb of air) within a margin of error. Pump gas changes from batch to batch. One batch, the premium may be +1.5% higher BTU. The next, regular may have +1.2% higher. They're the "same" for practical purposes.

 

[y_p_w]

The energy content of gasoline may have more to do with the crude oil used. However, that's kind of hard to control. You get what you get and refineries don't exactly worry about it. A lot of crude and finished gasoline are considered commodities where they're just required to meet a range of specifications. A lot of it is mixed together after being delivered through pipelines.

 

[odie]

All brands of high octane in this video have higher detergent level than the 87 . Is old , so not sure if detergent levels would still apply . Go to 2:19 in the video and watch rest of video where brands are tested at a lab for detergent levels . The whole video is worth a look .

 

[ammolab]

I wouldn’t buy premium for “more” detergents. I want “enough” for sure but will I pay 60 cents per gallon for “much more than enough”. Nope. It will do nothing for DI valve deposits, and I haven’t had an engine problem in the last 45 years of driving that more than enough detergents would have either prevented or corrected.

 

[odie]

I'll pay the extra . Not going to put too much of a dent in the wallet . Also been using it close to 15 years for the small engines and old habits are hard to break .

 

[Burt]

Regular and premium will have the "same" energy potential (BTU/lb of air) within a margin of error. Pump gas changes from batch to batch. One batch, the premium may be +1.5% higher BTU. The next, regular may have +1.2% higher. They're the "same" for practical purposes.

Source and justification that regular and premium have same btu content? I see lots of unsupported statements of this but it would have to be coincidental that btus lined up.

 

[RDY4WAR]

Source and justification that regular and premium have same btu content? I see lots of unsupported statements of this but it would have to be coincidental that btus lined up.

Does Premium Gasoline Have More Energy Than Regular?

No, the BTU/lb of energy of 91-93 premium is the same as regular 87. (within MoE) The heavy aromatic content is slightly different (same concentration) to get the higher octane value. Distillation, flame speed, burn rate, vaporization, etc... all practically the same.

bobistheoilguy.com

MIT School of Engineering | » What’s the difference between premium-grade and regular gasoline?

engineering.mit.edu

 

[dguzzi]

You mean they don't call it "Ethyl" anymore?


I know....it was a tetraethyl lead thing. I think even regular had lead in it. But grandpa called premium ethyl for years after lead went out....

 

[WylieCoyote]

My poor coworker has been listening to somebody who's really not educated on this subject matter. I found out last week she runs 93 octane in all of her lawn equipment because somebody told her it contains more power than 87. I sent her links to a few things to read explaining how and when 93 octane benefits you and when it's just a waste of money. At the end of the day she's not spending that much money buying enough 93 to run in her lawn mower and other equipment, but it was just the fact that somebody so badly misinformed her that had me fired up on principal.

 

[GSCJR]

I ran Shell V-Power 91 in all my seasonal equipment until it was no longer ethanol free. I may keep running it in my bike though, I haven't yet decided on that one.

 

[Exhaustgases]

High octane = fuel resists high temperatures in combustion space, better than lower octane.
The inverse is Cetane.

 

[y_p_w]

You mean they don't call it "Ethyl" anymore?


I know....it was a tetraethyl lead thing. I think even regular had lead in it. But grandpa called premium ethyl for years after lead went out....

Ethyl was a trademark of the Ethyl Corporation, which was a joint venture of General Motors and Standard oil of New Jersey (aka Esso, then Exxon).

I guess it's like some brands of premium fuel. Chevron has branded their premium as "Supreme" (along with their motor oil) and I've witnessed some people referring to getting "Supreme" outside of Chevron stations.

 

[y_p_w]

Source and justification that regular and premium have same btu content? I see lots of unsupported statements of this but it would have to be coincidental that btus lined up.

I don't know if it lines up perfectly, but for the most part there's nothing where different octane ratings inherently have more or less energy content. Now one way to boost octane rating is to use an oxygenate, and that will inherently bring the energy content per unit volume down. However, it's my underatanding that the majority of unleaded fuel sold today is meant to be blended with the max 10% fuel ethanol. So that's essentially a wash.

There's going to be a fairly substantial range in energy content simply on the basis of normal production variation from any number of factors including the particular crude oil source available. However, I'd think it's something that's kind of hard to test given that fuel is a commodity thats sent in pipelines, and where commodity fuels from different refineries are commingled all the time.

 

[Rmay635703]

I'll pay the extra . Not going to put too much of a dent in the wallet . Also been using it close to 15 years for the small engines and old habits are hard to break .

I’ll pay a little extra to get efree 87 for a mower but not almost double the price of the cheap stuff for premium