Carburetor issue
 

I have a 1965 389 that was just rebuilt ; bored .030 over and I went through break in process but I cannot keep engine running with current carburetor; I put a 570 holleystreet avenger on it but it will not idle; runs fine as long as throttling the carb; I put new fuel filter on it and new adapter plate but still have same issue; don’t know what I’m missing
thanks