Great. Sounds to me like it may be accelerator pump timing.
See what you find and there may be other opinions here.
If its not, then maybe worth going back and investigating the initial throttle position.
If this link still works, look at the illustrated side bar on that page. It explains it better than I can. It's in Urich & Fisher Holley Carburetors & Manifolds
If you want to experiment with that, but not drill or chamfer, there's a few other ways to do it.
1. Your QF may have an 'idle eze' or you can crack open the secondary idle position just a hair.
2. Change the idle speed by bumping up or reducing the initial timing a couple degrees.