I played with that a little. Even when I set it to run REALLY rich to see if I could peg the O2's, I couldn't. IT just started backfiring from all the extra fuel in the exhaust tract. Its almost like .71V - 0.8V is the limit at high RPM. At low RPM I've seen them touch .95V, but they dont work that way at high RPM for some reason. I want to get some wideband O2's and put them in the car though.. I am running ~11:1 at this boost level though. I have a fuel map editor that displays in A/F ratios rather than percentages of enrichment.
: what do you think that equates to in terms of A:F? My guess is somewhere around 13:1 to 14:1... just a guess though. I'd do some tuning on a dyno with an actual wide-band O2 sensor if I were you...