Ford Guy...I understand your frustration, the BBD carburetor and feedback system is complex, and the ECU/MCU and vacuum circuit interface with the distributor can be confusing as well. There are two concerns here:  A/F ratio of the fuel mixture burn at the emissions testing rpm and the ignition performance at these same speeds.  Also, the engine has several emissions related components, including the Pulse-Air system, the cat, an EGR valve and vacuum circuit plus an O2 sensor. The igni