Carb problems
 

I have a Holley 4150 double pumper 750 cfm with mech secondaries on a 351w I had it running seemingly fine but every time you hit the gas it would pop I was told it was running rich fiddled with it a bit and eventually bottomed out the float screws and idle screws and gave it a vacuum leak it ran better but not nearly good enough still popping no matter what the timing