I'm not sure exactly what you are asking?
In any case, the large main airbleed Chevy q-jets are very difficult to tune, especially with modern fuel blends on high performance applications. We have had excellent success installing the smaller main airbleeds, and our custom jet/metering rod set-ups.
Basically, the large main airbleeds add too much emulsion air to the main system, and require HUGE main jets and very small metering rods to get a decent fuel curve. They still don't work nearly as well as when the smaller main airbleeds are installed right from the start......Cliff