1. Welcome to Tacoma World!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tacoma discussion topics
    • Communicate privately with other Tacoma owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

Premium Gas and Better MPG

Discussion in '4 Cylinder' started by Taco 22, Sep 30, 2014.

  1. Oct 18, 2014 at 6:13 AM
    #41
    maineah

    maineah Well-Known Member

    Joined:
    Mar 24, 2011
    Member:
    #53641
    Messages:
    6,585
    Gender:
    Male
    First Name:
    Tim
    Maine
    Vehicle:
    4X4 SR5 V6 6spd
    They no longer say performance gains in the manuals. Most lawn mowers are 5HP so with the extra 3HP you still would not be able to cut the grass. 91 octane has less heat value that 87. Ethanol is used in race cars to combat spark knock.
     
  2. Oct 18, 2014 at 6:15 AM
    #42
    maineah

    maineah Well-Known Member

    Joined:
    Mar 24, 2011
    Member:
    #53641
    Messages:
    6,585
    Gender:
    Male
    First Name:
    Tim
    Maine
    Vehicle:
    4X4 SR5 V6 6spd
    2 MPG is like 10% gain highly unlikely.
     
  3. Oct 19, 2014 at 9:06 AM
    #43
    Indy

    Indy Master of all I survey.

    Joined:
    Sep 15, 2013
    Member:
    #112518
    Messages:
    2,582
    Gender:
    Male
    My mustang gets worse mileage on 91 than 85. Ive tried it 2-4 times, each time i get the lower end of what i usually get. 19-22 normally, 18-19 on the higher octane. I havent figured that one out yet.
     
  4. Oct 19, 2014 at 1:09 PM
    #44
    midwestfourwheel

    midwestfourwheel Member

    Joined:
    Oct 4, 2014
    Member:
    #139639
    Messages:
    18
    Gender:
    Male
    Junior Damato who writes a syndicated column as the Car Doctor addressed this topic today in our newspaper. Although mentioned as possible, he makes no claim of improved MPG. He does however make strong argument for occasionally running a tank of higher octane fuel thru one's vehicle for purpose of 'cleansing' the internal engine components by virtue of higher combustion temperatures.

    On our last trip thru South Dakota was surprised to find mid grade fuel less costly than regular; until noting the regular was alcohol free.
     
  5. Oct 19, 2014 at 1:38 PM
    #45
    worthywads

    worthywads Well-Known Member

    Joined:
    Jun 25, 2011
    Member:
    #58841
    Messages:
    5,345
    Gender:
    Male
    Peoples Republic of Boulder
    Vehicle:
    05 5-lug access I4 Stick, 70 Challenger Vert
    Yep, if 87 is E10 and 91 is E0 there is around 3-4% gain. 1 mpg is understandable.
     
  6. Oct 21, 2014 at 1:45 PM
    #46
    wolftree21

    wolftree21 Active Member

    Joined:
    Oct 13, 2014
    Member:
    #140255
    Messages:
    27
    Gender:
    Male
    First Name:
    Rick
    Ohio
    Vehicle:
    2011 Regular Cab 4 Cylinder
    Bilstien 5100s. Toyota rear spring TSB upgrade. 5th rear spring added. Michelin LTX/MS-2 265-70x16 Addco rear anti-sway bar.
    Over a long period of years I have noticed a MPG and performance gain in all but one vehicle by using higher octane fuel. In every case the increased gas mileage has offset the higher cost. The performance is noticeable.

    You can bet that NHRA and NASCAR events are not ran on 87 octane.
     
  7. Oct 21, 2014 at 3:48 PM
    #47
    1980

    1980 Well-Known Member

    Joined:
    Apr 14, 2010
    Member:
    #35307
    Messages:
    716
    Gender:
    Male
    The Dust Bowl
    This is because the high compression engines used need higher octane. Remember that octane rating is a measure of resistance to pre-ignition. However, our Tacoma's run perfectly well on 87 octane (or 85 octane at higher altitudes).
     
  8. Oct 21, 2014 at 4:29 PM
    #48
    wolftree21

    wolftree21 Active Member

    Joined:
    Oct 13, 2014
    Member:
    #140255
    Messages:
    27
    Gender:
    Male
    First Name:
    Rick
    Ohio
    Vehicle:
    2011 Regular Cab 4 Cylinder
    Bilstien 5100s. Toyota rear spring TSB upgrade. 5th rear spring added. Michelin LTX/MS-2 265-70x16 Addco rear anti-sway bar.
    There is not a cheaper performance/gas mileage booster than using 91 octane. Spend an extra $0.20 and find out yourself.
     
  9. Oct 23, 2014 at 8:58 AM
    #49
    Indy

    Indy Master of all I survey.

    Joined:
    Sep 15, 2013
    Member:
    #112518
    Messages:
    2,582
    Gender:
    Male
    And neither does the space shuttle. But it, a nascar engine and a regular car engine all have different requirements.

    If your engine isnt nocking the higher octane does nothing. Physics is what it is.
     
  10. Oct 24, 2014 at 12:50 PM
    #50
    DGXR

    DGXR Well-Known Member

    Joined:
    Sep 1, 2009
    Member:
    #22094
    Messages:
    2,204
    Gender:
    Male
    First Name:
    Friend
    Sacramento, CA
    Vehicle:
    2006 2.7L SR5 2-wheel drive
    I only run 87 octane in my Tacoma 2.7 2TR-FE because that's what the manufacturer calls for. Yes I have tried 89 and 91 octane but it made very little if any difference in the 4cyl, while the v6 is designed to take advantage of the higher octane. (Don't they both have knock sensors?)

    Anyway, over the 5 years and 70,000 miles I've had my Tacoma... assuming identical driving conditions, fuel from higher end stations (Chevron, Shell, Unocal, etc) gives slightly better MPG numbers than fuel from discount stations (ARCO, Rotten Robbie, Bob's Petrol Shack, etc). Although ARCO was certified as a top-tier brand a little while back (ARCO is now owned by BP), the ARCO 87 octane fuel just does not give me the same MPG numbers as Chevron 87. Since it's all the same octane, the difference must be in the brand's proprietary additive formula... Chevron just burns better in my truck than ARCO.

    Since the cheaper fuel gives fewer MPGs and the pricey fuel gives better MPGs, I did the math... in cents per mile on fuel cost alone, the cheap gas is technically a better deal, for now. A few years back, the price difference between these two brands (ARCO & Chevron) used to be only 20 cents per gallon but lately it's been close to 40 cents per gallon. I will continue to buy Chevron because the difference is only about one cent per mile when factoring in the better fuel economy for the pricey brand, and I like knowing this fuel has been proven to burn better in my engine.

    Finally, I call BS on the "extra cleaning" provided by higher octane gasolines. All grades have cleaning additives as required by law, the only difference is the octane rating. If you want to pay for a cleaner engine, don't put the wrong grade of fuel in your vehicle. Instead, buy a dedicated cleaning product such as Techron or similar. Some people say the new Seafoam intake tube nozzle applicator system is effective in cleaning their engines. Or just take it to your local trustworthy garage and pay for a fuel system cleaning service, and you will get a receipt document proving that your engine was cleaned. It is a waste of money to put high octane in a unmodified engine designed for regular and the manufacturer recommends regular grade.
     
    Last edited: Oct 24, 2014
  11. Nov 10, 2014 at 10:59 AM
    #51
    Indy

    Indy Master of all I survey.

    Joined:
    Sep 15, 2013
    Member:
    #112518
    Messages:
    2,582
    Gender:
    Male
    Pretty much every modern engine will have knock sensors and will advance as far as they can until the detect detonation, and then back it off. After a certain point advanced timing doesn't do anything good so there's a limit to what an engine will do. Higher compression engines generate more heat from the compression itself which can cause pre-ignition, which the higher octane is needed to combat. The compression and timing advance is what generates extra hp, not the octane itself, it just lets the engine work.

    Their isn't any 'extra heat' from higher octane that will clean squat, so ya BS. But an expensive high octane *may* have extra detergents etc that may do a little cleaning, but doubtful imo.

    And if your spark system isn't working correctly running a higher octane than needed can actually decrease mpg and hp. A useable spark with normal octane may be a weak spark with high octane.

    Once you get past physics, if you feel a difference that violates actual physics, I refer you to my tagline :laugh:
     
    Last edited: Nov 10, 2014
  12. Nov 10, 2014 at 11:06 AM
    #52
    FatTony415

    FatTony415 Well-Known Member

    Joined:
    Sep 24, 2013
    Member:
    #113196
    Messages:
    136
    Gender:
    Male
    First Name:
    Tony
    San Francisco, CA
    Vehicle:
    '20 DCSB 4x4 TRD Off Road
    Stock for now
    "The 1GR-FE is the 4.0 L (3956 cc) version, designed for longitudinal mounting in RWD and 4WD pickup applications. It has a 94 mm bore and a stroke of 95 mm. Output is 236 hp (176 kW) at 5200 rpm with 266 lb·ft (361 N·m) of torque at 4000 rpm on 87 octane, and 239 hp (178 kW) at 5200 rpm with 278 lb·ft (377 N·m) at 3700 rpm on 91 octane. This engine features Toyota's VVT-i, variable valve timing system on the intake cam and a compression ratio of 10.0:1. Service weight, including fluids, is 166 kg (366 lb)."

    http://en.wikipedia.org/wiki/Toyota_GR_engine#1GR-FE
     
  13. Nov 11, 2014 at 2:49 PM
    #53
    tacomathom

    tacomathom Well-Known Member

    Joined:
    May 29, 2010
    Member:
    #38040
    Messages:
    874
    Gender:
    Male
    First Name:
    Tom
    It's not new, it's not Mexico
    "If it is in Wikipedia then it must be true and you can't question it"
    Abraham Lincoln
     
  14. Nov 11, 2014 at 4:04 PM
    #54
    RKCRUZA

    RKCRUZA Well-Known Member

    Joined:
    Oct 3, 2014
    Member:
    #139609
    Messages:
    1,076
    Gender:
    Male
    First Name:
    Bob
    Placerville, Ca
    Vehicle:
    2015 TRD Pro in the Garage!
    You have the same problem I have....You Live in California! I forget the exact number, but Ca. has around 6 different formulas for gas depending on the area you live in, and the time of year. I get better mpg from the gas I buy here in the Mtns. than I do if I buy gas in Sac or the Bay area....also a huge difference between summer and winter gas around here.
     
  15. Nov 12, 2014 at 10:59 AM
    #55
    Indy

    Indy Master of all I survey.

    Joined:
    Sep 15, 2013
    Member:
    #112518
    Messages:
    2,582
    Gender:
    Male
    Winter gas always sucks. 1% less smog but you burn 20% more gas, math doesn't quite add up.
     
  16. Nov 12, 2014 at 5:27 PM
    #56
    worthywads

    worthywads Well-Known Member

    Joined:
    Jun 25, 2011
    Member:
    #58841
    Messages:
    5,345
    Gender:
    Male
    Peoples Republic of Boulder
    Vehicle:
    05 5-lug access I4 Stick, 70 Challenger Vert
    It is summer blend that cost more to reduce smog.

    Cold weather is the penalty, winter blend is a minor factor.

    Winter gas alone causes 1.7% reduction in mpg.

    http://www.ehow.com/info_12071245_low-gas-mileage-winter-due-blending.html

    My mpg dropped from 30 to 20 on the same gas overnight going from 60F to 15F.
     
    Last edited: Nov 12, 2014
  17. Nov 13, 2014 at 7:50 AM
    #57
    DGXR

    DGXR Well-Known Member

    Joined:
    Sep 1, 2009
    Member:
    #22094
    Messages:
    2,204
    Gender:
    Male
    First Name:
    Friend
    Sacramento, CA
    Vehicle:
    2006 2.7L SR5 2-wheel drive
    33% reduction in fuel economy caused solely by lower temperatures? Are you sure?
     
  18. Nov 13, 2014 at 4:01 PM
    #58
    worthywads

    worthywads Well-Known Member

    Joined:
    Jun 25, 2011
    Member:
    #58841
    Messages:
    5,345
    Gender:
    Male
    Peoples Republic of Boulder
    Vehicle:
    05 5-lug access I4 Stick, 70 Challenger Vert
    Yes. Including slow congested traffic. Wouldn't be as bad if I had a long commute but at 0-15F engine isn't even warmed up by the time I get to work.

    Certainly not winter gas.
     
    Last edited: Nov 13, 2014
  19. Nov 13, 2014 at 4:07 PM
    #59
    DGXR

    DGXR Well-Known Member

    Joined:
    Sep 1, 2009
    Member:
    #22094
    Messages:
    2,204
    Gender:
    Male
    First Name:
    Friend
    Sacramento, CA
    Vehicle:
    2006 2.7L SR5 2-wheel drive
    Oh I see... "open loop" operation is definitely a MPG killer :(
     
  20. Nov 14, 2014 at 8:05 PM
    #60
    keakar

    keakar Well-Known Member

    Joined:
    Oct 2, 2014
    Member:
    #139537
    Messages:
    5,259
    Gender:
    Male
    First Name:
    karl
    louisiana
    Vehicle:
    2006 4runner sport 4.7L V8 (white)
    used to have - 99 2.4L I4 5 lug & 04 prerunner v6
    bottom line is you do get better mpg from premium gas but the amount you save is more then offset by the higher price you pay for it so price you pay per mile driven is actually about 2 cents more per gallon paid then you will save because of more power and better mileage from the higher octane.

    so in effect its a wash so there is no negative to using premium at all and you "almost" get your money back from the higher cost of it with the benefits of increased mpg and power you get from using it.

    for small underpowered 4 stroke water cooled engines its better to use premium but its hard for most people to get over the sticker shock at the pump to use the premium gas and as prices go up and down it may cost you as much as a nickel or more a gallon at times above and beyond any cost savings benefit you see so constantly checking the price differences is key.
     

Products Discussed in

To Top