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Thread: happy gas for mfi

  1. 03-19-2021, 12:24 PM #1
    sanders
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    happy gas for mfi

    What fuel that is somewhat readily available works best in a mfi "S", '69 in particular? My problem is that using 90 octane non-ethanol requires such a rich AFR that I cannot bring down the idle enough to avoid the dreaded surge brought on by the rpm transducer. I prefer non-ethanol but 93 octane is available if that works. Thanks for your suggestions.
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  2. 03-19-2021, 01:03 PM #2
    Arne
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    I would think that non-ethanol 93 would be a good choice for a 2.0S.
    - Arne
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  3. 03-19-2021, 01:42 PM #3
    sanders
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    93 only available with corn syrup around here.
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  4. 03-19-2021, 04:12 PM #4
    Arne
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    OK, I mis-read what you were saying. The reverse is true around here, non-ethanol is only generally available in 92, which is not ideal for my low compression '72T.

    So I'm assuming that the 90 octane needs an over-rich mixture to keep it from pre-ignition? If that's true, I'd use the 93 with ethanol. I too would prefer non-ethanol, but if you can't buy that...
    - Arne
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  5. 03-20-2021, 06:04 AM #5
    72targa
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    What’s your compression ratio?
    Peter Kane

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  6. 03-20-2021, 09:03 AM #6
    sanders
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    9.9 stock S
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  7. 03-20-2021, 09:12 AM #7
    Theunz
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    I use 91 non ethanol in my stock 69 S with no issues. It does however idle at about 1100 most of the time unless I blip the accelerator pedal, than it will drop to about 6 or 7 hundred.
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  8. 03-20-2021, 06:47 PM #8
    Orval_F
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  9. 03-20-2021, 06:57 PM #9
    NZVW
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    What percentage of Ethanol is in the gas in the USA ???????
    Mark
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  10. 03-20-2021, 07:03 PM #10
    karlusmagnus
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    Quote Originally Posted by NZVW View Post
    What percentage of Ethanol is in the gas in the USA ???????
    I think it averages at about 10%.
    Karl: E911SR #792 ; RG #420 ; GS #7

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