i notice on datamaster that my even with
low blm numbers my o2 sensor is reading
between .100 mv - .650 mv which would
say i am on the lean side and my butt meter
says its lean ( the more you push on the gas pedal
it takes a moment for power to accelerate )
am i correct in that low blm's are normally a
rich condition ?
mike

In closed loop the O2 voltage just toggles from high to low. The realtionship of rich to lean as a function of that, takes the ecm to interupt. High Bls means the ecm is correcting for a lean condition, and low BL means things are rich, and it leaning things to compensate.

The stock O2 is poor for saying anything more then things are richer or leaner then 14.7.

i have a lambda meter as well
and it shows cruise a/f's of 14.8>15.2
i also have a bad lean spot on throttle
tip in from lower speeds or high vacuum
conditions where it jumps as high as
17.1 for a moment .. i have decent a/f on the lamda
under harder accelerations from 11.6> 12.7
there are two tables to deal with this as
i see it using tunercat software , one being accel vs map
and accell vs tps .. is there a preferred choice ?
this is on a 747 ecm .
mike