Engine stalls under hard braking

hello
i finish to convert my 71 nova to disc brake (only the front )
during the test driving i noticed : running fast and trying to stop the car asap make the engine stall , and its difficult to start the engine right after


i also noticed , way before the convertion , wild turn or donuts attempt make my engine stall as well , and the same , its difficult to restart the engine

any idee? thanks


my engine start every first crank in general , even if i dont use it for two week
350 with edelbrock 650 cfm
power steering