Drag strip launch problem
Rumblefish that's basically what i meant by mods with your reference of the primaries being uncovered at high g's... since the bowls are oriented front-to-back the fuel is probably sloshing to the back and screwing up fuel delivery to the primary boosters. Carters have very shallow angles that the boosters go into the venturis which is why they are more sensitive to float levels than Holley-type designs. It's a simple problem but tough to fix it would be much easier just to switch to the demon the OP has.
I've been running my AFB for years and i love it for the street but when i go to the strip or make sharp turns at high speed its faults become obvious.