has anyone had this problem before? it comes and goes and its annoying. it seems to happen most when i drive through my neighborhood. and never happens at full throttle. anything would help

 

Is this an out-of-the-box Holley carb, like a 4150/4160? If so, the metering plates and likely the air bleeds probably need some tuning to get the right mixture for the transfer circuit. Most bolt-on carbs are not very well set up for anything but a stockish 350, and are only marginally good at off-idle and transfer to the main circuit even in those applications.

 

its an 1850s 600cfm that i got off of craigs list 2 years ago. i built the car from the ground up but im new to carbs. i dont know where to go from here and i hate wasting money throwing parts at stuff. im hoping for a tip or two on what will smooth out the problem. from what ive read about carbs, trial and error is half the process, but money is tight with my wife starting college so i would like to spend it wisely