Super-charged 408 stroker engine stalls on Hard Braking

[Chuwers]

The car runs great on the street. On VERY hard braking, the engine bogs down and stalls. Here's the essentials and symptoms:
Vortek style centrifugal compressor, Mighty Demon Blow Through (BT-750) Carb, mild cam, nothing too radical, 550 hp.
Initial suspects: 1) vacuum loss, or 2), fuel sloshing forward, up into the Vent Tubes and spurting into the throat.
Put car with wheels just off the ground. Put into gear and run up to 3,000 rpm. Slam hard on brakes and the stall does not occur. Neither in Fwd or Reverse.
Seems to preclude vacuum loss?
Thought about sloshing fuel, so put "duck bill" baffles into the float chambers to avoid fuel sloshing up into vent tubes. Didn't help, still stalls
Float levels are set just a wee tad below the centerline.
Any thoughts on cause, or diagnostic tests I might run?

 

[AeroCoupe]

Dynamics is kicking your ass. I would go straight to the fueling and specifically the carb. A kit May fix it but it still may be fueling when you have to switch to braking and it’s flooding the motor. This or you need to send the carb off to a reputable shop to go through it.

I have a Carb Shop 830 CFM carb that is set up for road racing and it works way better on the street than it did when it was a stock Holley 750. Not saying they are the go to for your application but there are shops out there specialize in this type of stuff.