NA 4.6 with cams stage 1 ...best AFR?

Discussion in 'SN95 4.6L Mustang' started by east_sidaz40, Nov 4, 2009.

  1. east_sidaz40 New Member

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    Hi,

    Where should i keep my AF ratio at?
    99 GT stage 1 ported heads + cams.
    12.0 -12.5 ?
    I want a safe Ratio for NA
    east_sidaz40, Nov 4, 2009
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  2. oxfordgt New Member

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    12.5-13.0 for best power. Stock is already 12.0. The tune will be safe at 13 as long as you keep the timing in check so you don't detonate.

    13.0:1 is always the best a/f ratio for power. Even on my car that makes 700rwhp at 23lbs of boost is tuned to run 13.0 at WOT but I spray meth on top of that the keep it safe.
    oxfordgt, Nov 4, 2009
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  3. bhuff30 Founding Member

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    Yup, right on. I would probably shoot for 12.9:1-13:1 on an NA engine.

    The stock tune on my 97 starts around 13.4:1 in the mid range and drops to about 12.2:1 at high rpms. Just terrible.
    bhuff30, Nov 4, 2009
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