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[ultrafxr]

From the sert manual, page 3:
"Tuning with Closed-Loop
Example: Using calibration 141NX001. Looking at 1750 rpm and 40 kPa, the AFR table shows
14.6 and the Closed-Loop Bias table shows 447mV. With these values, the ECM will be in closed-loop
operation and will control to approximately 14.4. In order to change the fuel delivered to the engine in this
condition, the Closed-Loop Bias table would be used. 500 mV will make the mixture slightly richer, and
400 mV will make the mixture slightly leaner."

Question:  is there any way to determine the relationship between the mV value and the afr.  In the example above if 447mV = 14.4 afr can we determine the afr using 500mV by some type of calculation alone.

[Unbalanced]

ultrafxr I couldnt when we first messed with it without a dyno because it depends on the cam and when it comes in and when it is efficient and when it is not.   what i mean is how volumetric efficient the head and cam are together depending on the rpm and mV

Previously the best we ever got the fuel to be using the closed loop mode in version 4.60 was 14.2 to 1 at 768 as the setting in the box.    The 14.6 in the fuel table just tells the ECM to look to the  closed loop table in this case to get what its fuel setting should be.

I dont know a way without mapping it one time on the dyno and changing the numbers to see if you could get a correlation.   Problem there is your usually using a muffler sniffer vs. a sensor at 2 inches off the head.

You might consider a daytona twin tech system to give you afr to track it if you wanted to get it where you wanted it.

[Ed Ramberger - One_Screamin_Eagle]

.450 mv = 14.7
Setting in the 739 range you will see 14.2 - 14.4
Setting lower than .450 - you'll see 14.7 14.8's

I set all mine in the 739 range because 798 is out on the edge of the sensor's range.

[WVULTRA]

Haven't had it on a dyno for true afr, but setting the F&R CLB Tables to max (798) sure stopped the excessive heat being generated during slow speeds and stopped for traffic!  And still getting excellent mpg.