Edelbrock Fireball!!!

I installed a new Edelbrock 4bbl carb and noticed that when I turn it over I get a huge fire ball out the top of the carb. At first I considered timing, after double checking I still get the fireball and a puff of white smoke, and engine wont idle, if I pump the gas I get loud back fires. Now I did notice that last night on the back of the carb is a port for the power brakes ( about the size of a nickle) this is not pluged. I know if comes with a plug but you know how those small parts run away. Can this create such a vaccum issue that the carb blows fire like this? Or is that just something I should plug but has no effect on the engine turning over?



Thanks FABO