What's up with 88 Octane gas and why aren't we all using it?

GrayRyder

Wandered in by accident
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Minuteman
  • Feb 10, 2017
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    In SW Pennsylvania at convenience chain called Sheetz is selling 88 Octance gas for like .30 cents cheaper than 87. What's up with 88? Is it no good for engines or what?
     
    Don't know. It's not an overstock scenario. THey have it at that price all the time. Figured one of the hide's famous petrochemical engineers would have some insight.
     
    Convenience chain called "Sheetz"...

    I think that answers everything. Don't eat the microwave burritos.
    The food is actually pretty good (for fast food). Not your typical heat lamp crap.

    OP, I've seen the 88 but I don't know what's in it or what the mileage is like. Ethanol should be higher octane, I would think, unless maybe it's stupidly low octane gas mixed with ethanol to bring it up to 88?
     
    The 88 is usually cheaper and has ethanol in it. (Or a higher percentage of ethanol.) If your car runs fine on it, use it, BUT be aware that there are less BTU's per gallon in oxygenated gas and your motor may not deliver quite as high fuel economy. Often a catch-22 scenario where the fuel is cheaper but yields less power, therefore less fuel mileage. YMMV.
     
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    In SW Pennsylvania at convenience chain called Sheetz is selling 88 Octance gas for like .30 cents cheaper than 87. What's up with 88? Is it no good for engines or what?
    We have Sheetz local. They advertise the cheap stuff but never seem to have it available. Sheetz is a real shithole, and almost always a dime higher than anyone else. I just filled up at Sam's Club for $3.79, Sheetz, which I affectionally refer to as Shits, is $4.09
     
    Real gas burns at a stoichiometric ratio of 14.7 parts air to 1 part fuel.
    Ethanol burns at 9 parts air to 1 part fuel
    Methanol burns at 6.5 parts air to 1 part fuel.

    So what happens with today's automatic regulating fuel injection is that you get 1/2 the MPG when using an alchohol (roughly) vs. gasoline.
    Yes, your fuel injection vehicles automatically adjust themselves to correct rich/lean mixtures.

    Is it any wonder alcohol is cheaper ?