1981 Pontiac Bonneville Olds 307 seems like it misses

I put this engine into an 85 firebird therefore all the computer stuff has been removed. I have a 600cfm carb on a performance intake and also a competition camshaft. The problem is that the car seems like it is missing when I push down on the gas. A gradual accelleration will eliminate to some degree that problem. I've pulled the plugs and they all seem fine. I'm wondering if this could be a plug wire issue, perhaps getting some crossover near the distributor? Also to note, my plugs actually come off or loosen occasionally at the distributor. But, even when they are all on this continues to happen. Any suggestions would be helpful. Thanks