Swt SS

I have a 1987 bertillia that had a tbi v6 engine in it, I have installed a sbc 350 with a carb. in it now. I am using the orig. 3/8 fuel feed line from the tank, no return. I am also using a mechanical fuel pump, I am getting fuel to the carb itself, but no fuel is going into the carb. pump is brand new, I checked and I am positivity getting fuel to the carb. I used this same carb...edelbrock 600cfm on my LS 5.3L and it worked great. any ideas what could cause no fuel getting into the carb?....thanks.