Contour Enthusiasts Group Archives Forums Modifications Duratec Performance safc fuel table

Just to clarify, if you try to make changes at less that 100% throttle setting, then pcm may undo the changes as it learns.
So just work with the 100% throttle setting.

With a wideband mounted in a stock O2 sensor port I'd shoot for about a 12.8-12.9:1 A/F unless you start to hear evidence of a ping or loss of power under load. You'll probably be safe to as high as 13.2:1 on this engine if everthing else is in good shape (low carbon buildup in the cylinders, new fuel filter, clean air filter). But I wouldn't set it above 13:1 if you mount your sensor in the stock location. Also, in the last 500 rpm, above 6500rpm you could set the air fuel back down to about 12.8:1 to keep things quiet since a lot of times the engine can be more sensitive to lean air fuel that high of an rpm.