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Entry Level Luxury Performance Sedans

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Comments

  • jkstew1jkstew1 Posts: 12
    What kind of gas mileage do you guys/gals get in city driving? What about highway driving? Has anyone used 89 octane in their vehicle?
  • shiposhipo Posts: 9,152
    Using 89 octane fuel in a BMW is a fool's economy. The fact is that while the engine will run perfectly well, it will not yield as much power nor deliver as much fuel economy. Said another way, while each individual tank of fuel will cost less, you'll be filling up more often and spending more money as a result.

    Best Regards,
    Shipo
  • louisweilouiswei Posts: 3,717
    Does BMW require or recommend 91 octane?

    If it's required then they can void the powertrain warranty if they want to play hardball. If it's only recommended then like shipo said, it's still a fool's economy.
  • shiposhipo Posts: 9,152
    Per my manual:

    Fuel specifications

    The engine uses lead-free gasoline only.
    Required fuel:
    - Premium Unleaded Gasoline, min. 91 AKI
    - AKI = Anti Knock Index

    FWIW, I believe that I read elsewhere in the manual that lower grades were acceptable in an emergency, however, performance would suffer.

    Best Regards,
    Shipo
  • scottm123scottm123 Posts: 1,501
    I agree 100%.
    I've found this to also be true in my 06 Acura MDX.
    I have done nothing but 91 or higher in my 07 G35.

    The money saved at the pump by choosing a lower grade is only put in the tank later, when you run dry quicker, since the engine runs less efficiently.
  • texasestexases Posts: 5,511
    I understand 100% the reasons for premium = better mileage, but does anyone have the numbers that show premium = 10% better mileage? That's about the increase needed to pay for it, right?
  • shiposhipo Posts: 9,152
    There was a study published some time ago that suggested that the reduction in mileage was more like 15%. That said, around here the difference in cost between Regular and Premium is more like 8%.

    Best Regards,
    Shipo
  • texasestexases Posts: 5,511
    I wish 8%, here it's $2.95 vs. $2.65, so about 11%...
  • blueguydotcomblueguydotcom Posts: 6,257
    Premium is about $0.20 more per gallon. 16 gallon tank, so you're paying $3.20 more per tank or maybe $160 extra per year. Seems like quite a bit until you realize you're paying about over 2k a year for gas ($3.00 a gallon). It's a drop in the bucket. If premium impacts your gas mileage even a little say +1 mpg, the cost is almost negligible.

    15000 miles / 23 mpg * $3.20 gallon = 2087
    15000 miles / 22 mpg * $3.00 gallon = 2045
  • kdshapirokdshapiro Posts: 5,751
    The real question is what does 87 vs 93 do to you cars performance, when your car is tuned for 93.
  • shiposhipo Posts: 9,152
    As I'm sure you well know (I suspect your question was rhetorical), burning 87 or 89 causes detonation (pinging) when the OBC sets the ignition timing at optimial settings. The detonation sensors report that fact back to the OBC which then retards the ignition timing, cutting fuel economy and performance in the name of protecting the engine from damage.

    Best Regards,
    Shipo
  • kdshapirokdshapiro Posts: 5,751
    Right on shipo, question was rhetorical. Most modern cars designed to run on premium fuel have knock sensors. Most car manuals say regular unleaded fuel can be used "in a pinch". But I can't figure why one would buy a car that requires premium and then want to put in regular unleaded as a matter of course to save a couple of bucks a year.

    As you eloquently noted, performance and possibly mpg will suffer.
  • oldcemoldcem Posts: 309
    I'm assuming you have a BMW. Have you noticed fuel economy suffer if you run premium gas blended with 10% alcohol. I have a Jaguar, and, the blended stuff cuts my gas mileage by about 2 - 3 MPG. Just wondering.

    Regards:
    OldCEM
  • oldcemoldcem Posts: 309
    My car consistently gets 20 MPG in city driving, and, about 26 running the interstate. Its an AWD with a 5 speed automatic and a 3 liter engine.

    Regards:
    OldCEM
  • circlewcirclew Posts: 8,353
    Do you guys remember Sunoco 260? It was/is around 105 octane. We didn't use it for more mileage back then but to boost HP.

    I believe this is still produced. It's gotta cost big bucks now (15$/gal.) but I am sure it would benefit on track day.

    Regards,
    OW
  • kdshapirokdshapiro Posts: 5,751
    That was before my time. cough, cough. Don't some Sunocos still have higher than 93 octane? I thought one of the stations along R9 did.
  • circlewcirclew Posts: 8,353
    I now recall it was called Cam2. There is a Sun Staion in Point Pleasant that sells it.

    Overview
    Sunoco 260 GT™ 100, which has the highest octane rating of any street legal fuel, is now available at selected retail locations.

    Sunoco 260 GT 100 is designed for high performance street cars, muscle cars, classics, street rods, motorcycles, karts and marine applications. Sunoco 260 GT 100 contains no metallic compounds to harm catalytic converters or oxygen sensors. It contains a comprehensive additive package for greater engine protection and reduced fuel system deposits. Sunoco 260 GT 100 is also compatible with virtually all two-stroke synthetic and mineral based motor oils.

    Sunoco 260 GT 100 Unleaded is available at selected locations throughout the
    U.S. In certain areas, Sunoco 260 GT 100 Unleaded is available under the CAM2 GTTM 100 label.

    I would NOT use this in my 330 or ina 335xi. I am near certain you would have warranty issue! (and you would go broke!)

    Regards,
    OW
  • shiposhipo Posts: 9,152
    The sad truth is that ethanol does not have the same number of calories per gallon as gasoline, and as such, your mileage will typically drop between three and eight percent when running on E10 as opposed to the same AKI rated fuel with no Ethanol. It doesn't matter whether you're talking about a Jaguar, a BMW or an old Dodge, they all suffer from in the same way due to the ethanol.

    Best Regards,
    Shipo
  • cdnpinheadcdnpinhead Forest Lakes, AZPosts: 3,237
    "Don't some Sunocos still have higher than 93 octane?"

    Could be, but so what, for those who actually leave the county they live in, or (OMG) the state. I'm going to posit that 93 octane availability is a very (very) local thing, and that one shouldn't depend upon it.

    I've fed my vehicle nothing but the highest-grade premium that's available in AZ (91, BTW) for its entire life. However, when I was going to (and in) Alaska recently, premium wasn't always available. Besides which, when you're above ~5000 ft you don't need it anyway.

    This is a Western thing. I realize that many (most?) who post here rarely get above 1000 feet above MSL, but out here it happens regularly.
  • laurasdadalaurasdada Posts: 2,591
    Here in the Boston area, 93 is readily available. Finding 91 is difficult. I can get 91 at a local-ish Sunoco station, but usually the 93 is cheaper just down the road!

    '13 Jaguar XF, '11 BMW 535xi, '02 Lexus RX300

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