Blow through with vacuum secondary Holley Carb.

TrailBeast said

Wait a dang minute, this is why those boost kits with the entire carb inside a pressurized box works, correct?

Click to expand...

Yeah and that's why a boost referenced fuel pressure regulator is required for blow thru applications.
A regular fuel pressure regulator feeding 7 PSI of fuel would have 1 PSI of fuel pressure to the carb if you're running6PSI of boost.