| to the program in order for it to keep from dumping tons of fuel when the recirc opens. In the ECU there is a 2-d table called TTP MAX. This table tells the ECU what the maximum total theoretical pulsewidth can be for any given RPM. The parameters in the factory ECU work pretty much spot on in all cases. When the BOV opens after letting out of the gas pedal, the additional airflow through the MAS will tell the ECU that a lot of air is entering the engine, but the ECU will not dump an according amount of fuel as the TTP MAX values limit what the total fuel delivery can be. It actually is beneficial to throttle response when it loads the intake down with a little extra fuel between shifts due to the BOV. When you are rapidly closing and opening the throttle, fuel falls out of suspension in the intake manifold due to the large swings in manifold pressure and additional fuel in the intake during a vacuum to pressure swing helps keep a good bit of fuel atomized to ensure a good burn. Acceleration enrichment also plays into this action but a little bit of extra fuel wont hurt - its just when you are lacking fuel during these throttle transitions that it really starts to hurt performance as it causes bogging and poor throttle response when rolling back into the gas. You can have a very heavy rich condition and it still have great throttle response, however, if it is even barely lean, throttle response will suffer dramatically. One thing I have commonly found on many Z's is the lack of proper preload tension in the BOVs. This will cause a lot of the issues that you describe in terms of stalling and backfiring. The small puff of carbon out the tailpipe is definately a factor of the BOV but it is really an inconsequential factor in terms of performance.
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