I got issues!

Gears are 2.72s i think but i have n 8.75 with 3.91s
Converter is stock
I didnt get the idle timing, i read some to let it fall where it falls total at 3k was more important?
Vac advance is hooked to ported vac port
Cam is Summit SUM-K50052

It runs decent at a light cruise from stop and gradually get into it but if you leave at wot it pops and carries on n tries to shut off

Sounds like the secondaries of that carb are opening before the engine can take it. Did you tighten the air valve yet? Can you disconnect the linkage so the secondaries will not open, to rule that out?