but how are you reading the narrow band sensors ?
since they are very non-linear if you just remap the 0 to 1 volt on a linear scale and average out the measurements I don't think this give you any idea if it's really running lean, rich or stoich
are you looking for reversal between lean and rich reading at a maximum interval to declare the engine running stoich ? (and if no reversal happen after the set amount of time then it is rich or lean)
do you have real world sensor output on a graph ? that would be interesting !
for the calibration, yes I have access to the gases because I have a very well furnished hacker space =)
I read about the LC-1 and the "wbo2" controller and I do not believe they are accurate, sure they show numbers and come in a pretty case but I just don't think they are accurate enough for an engine management sensors, if you read the extremely interesting document about the "Precision Wideband Controller" http://www.megamanual.com/PWC/index.htm
they say that you have to very accurately maintain and measure the temperature of the sensor using the heater, and also output with the sensor signal a "margin of error" signal for when the temperature goes to uncorrectable values (ice water splashing on the exhaust, or engine running more than 800 C )
also you have to apply current to the oxygen pump so the cell stays at 0.450V and it is the current value required to do that, that you read to get the air/fuel ration, and this current change for the same AFR if the cell is at a different temperature
I just don't think the LC-1 or the WBO2 controllers have all that working
you can get just the LC-1 controller with no display and no sensor that would be useful and almost cost effective but it's not good enough (or at least innovate motorsports isn't proving it's doing what it has to do to get accurate readings)
so we have to start over !
for starters, the LC-1 that my friend bought from IM themselves, doesn't come calibrated, they have a crude auto calibration, but I don't believe it works for better than 15% accuracy
good enough for the bling that an AFR gauge is but not for any kind of serious engine management
also I didn't say the Bosch 4.2 is a bad sensor but (and I can't find out where, right now) I read somewhere that the 4.9 was more tolerant of having high pressure exhaust gas blown on it, for example on the RB26 the oxygen sensor plug is right after the turbo outlet and right at the apex of a 90 degree turn in the pipe so the full blow of the exhaust is bearing down on the sensor , surely that would need a LSU4.9 to be accurate if what I read is true