If its running that rich, and blowing black smoke, then unless its skipping badly, its a carb problem.
A bad spark, either wires, distrib. or plug could cause one or more cylinders not to fire and let the gas blow out the back, but its most likely the carb.
Is it blowing the black smoke and smelling when it quits? I suspect that it's not. Dieing at speed and running at idle is almost always fuel delivery.
Which in most cases is the fuel pump or filter. Basically you are pumping enough gas to run the engine at idle, but not enough when you get up to speed.
In this case, you have replaced the pump, so unless you got a bad pump, not impossible, then its most likely the carb.
Right off the top of my head, it sounds like major float problems. Like the float is stuck.
At idle, it lets too much gas into the float chamber because it is not cutting off. But, since it is stuck in one position, it cannot open up enough when you start needing more gas and you run out at 30.
Having said all that, if the problems all started when you changed the fuel pump, I would take a hard look at it first.
If you changed the pump because of these problems, then its probably the carb.