[island911]

Originally Posted by Jeff Higgins

... Set per the numbers found in CMA, they pass emissions. And run like crap. Back then, of course, wide band O2 sensors were still just a dream, so CO2 was all we had. Today, with readily available wide band O2 sensors, we can merely drive on down the road and get A/F ratios real time, under a broad variety of operating conditions. When tested this way, it becomes painfully obvious that, when the CO2 is set per CMA, the poor things are just too lean.

Correcting that changes everything. Unfortunately, "everything" includes significantly increased emissions and, with it, that infamous MFI stink. They like to run on the rich side, even richer than carbs. When made to do so, they become an entirely different animal.

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Good points. I suppose i should note that my SC runs stronger w/o O₂ sensor attached, and dialed richer than OE spec. Still much leaner than the MFI or carb'd of course. Those things... I can't help but think of chasing an MFI car thinking "Porsche - Kills bugs fast" line - as the fumigation behind the car drops the bugs.