I would never run an FMU either...nor an AFC "hack." I'd run a hondata/uberdata, or an AEM EMS if I had the cash. The new hondatas have an autotune feature...hook up a wideband o2, pick an A/F ratio, and it will do the work for you. There is also a DIY standalone system that I heard about, it costs like 100-200 bucks in parts, and also has an autotune...but I haven't heard much about how well it works.
Also, are you running a larger intank pump, or an inline high pressure pump?
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2015 Ford Mustang GT Fastback - Ingot Silver - 6M - Performance Package - Gibson Catback, JLT CAI, FR 47lb injectors, BAMA E85 tune, Eibach Sportline, BMR wheel hop kit, UPR oil separator, Steeda shifter bushing/bracket
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