[66StangGuy]

if you cover the carb then it will die no matter what. if you cover the carb then you cut off the engines fuel. no vaccume through the carb will not allow the system to work to give the motor fuel.

im sure of your problem like i posted because i had the same issue. im almost posative the that secondaries are sticking open and giving the motor too much air\fuel then what you want.

back off the idle screw on the drivers side all the way out so the front throttle plates are closed. then start the car and see if it does the same thing. if it does then the secondaries are open.

if you try this and it works post your reply and i will help you with closing the secondaries.