Tweecer And Air/Fuel

Discussion in '94-95 5.0 Tuning' started by tjh566, Feb 15, 2007.

  1. tjh566 New Member

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    Ok Under the Scalars There is one called "Nominal AFR" I was under the assumtion this value what ever inputed the computer would try and target. My question is this, how does the computer know when it achives this if I set it to say 12.5, Because I thought the O2 sensors it reads off of only read rich/lean for 14.7.

    Or am I understanding how to tune the AFR All wrong? Do I just need to adjust the fuel tables to my needs AND have that at my desired value or what?
    tjh566, Feb 15, 2007
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  2. final5-0 Mustang Master

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    When you see all the talk about your air to fuel ratio ...........
    That is all about Open Loop

    When you see all the talk about O2's and adaptive strategy ...........
    That is all about Closed Loop
    The pcm ... NOT you ... controls the ratio here
    hence
    The Phrase ... Closed Loop

    If by chance you are looking at LAMBSE values ......
    That is NOT your af ratio

    LAMBSE is the commanded ratio from the pcm at any
    particular point in time and it changes due to various
    sensors sending data under various driving conditions

    If your concerns all stem from the af ratio .......
    You need a Wide Band to accurately make adjustments

    Without the WB ... you put yourself at risk by trying to change
    the values in the fuel tables.

    Did I help or just make you wanna ask more Q's :shrug:

    Grady
    final5-0, Feb 16, 2007
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  3. tjh566 New Member

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    I think I understand, but heres a question, I need my air/fuel ratio to be 12.5:1 for Forced Induction.. Do I just richen the fuel tables? until I hit my desired AFR, I do have a wideband.
    tjh566, Feb 17, 2007
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  4. final5-0 Mustang Master

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    No since in typing all that stuff twice :D

    See if this helps :shrug:

    http://forums.stangnet.com/showthread.php?t=685346

    12.5 ain't fat enough for forced induction!!!

    Grady
    final5-0, Feb 17, 2007
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  5. tjh566 New Member

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    oopsies for some reason I had that 12.5 in my head, just researched it agian and now I remember 11:1 is the safe number.

    And my new hard drive just died. So I lost the base tune I had made up and the EEC Analzyer that I bought, and various other important e-mails :(

    Anyways, Thanks grady always helpful as usual.
    tjh566, Feb 17, 2007
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  6. final5-0 Mustang Master

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    Don't Ya Hate It :chair:

    When that happens :rlaugh:

    Here is a little tip for you :D

    The cal file is not all that big
    and
    Its easy to save on a floppy or thumb drive
    if
    You can remember to do ... that is ;)

    Grady
    final5-0, Feb 17, 2007
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