(typed up for anyone that is turboing a car that didnt come t-ed originaly)
i was curious about this because none ive talked to has ever tried this before, and a few people even told me it wasnt possible
the car: 2000 ecplise gs, turbed using a mix of 4g63t parts & safc
the prob we were having: no matter how much we adjusted the safc, the ecu stayed ahaead of us in closed loop mode, netting my friend a $350 trip to the dyno that did NOTHING for us, except confirm that the a/f was 14.7 all the way to 4 grand, despite the safc being cranked all the way to the max adjustment
i finaly got fed up and i cut the front 02 signal wire, patched in the analog out #1 from the wideband , and adjusted the narrow band simulation map for that output so that 12:1 a/f fed a 14.7:1 signal to the ecu
result: the ecu took care of its own closed loop adjustments, and the safc prety much only tunes for idle and open loop.... most of the low rpm adjustments are zeroed, car maintains 12:1 all teh way across the rpm range
i was temptd to just disconnect the front o2, but decided to try this first, if my buddy still has the car next summer ill probably add a pressure switch to the system so that the car runs on the real o2 signal at 0 boost, and switches to the wb02 fake signal at 1psi or more ... for fuel efficiencies sake