Have replaced spark plugs and wires,Dist cap and rotor, new coil,Ignition module(because it was leaking black goo,but still ran fine at the time). At start up she will run great.Punch the gas and she goes as a 351 outta. When she warms up, she acts as if she missing on 1 or 2 cylinders. Any thoughts at all???

 

Choke completely open?
EGR stuck open or the passages/gaskets burnt out underneath the carb?
Check all vacuum hoses
Check PCV valve.

 

Thanks!! Will check vacuum connections and choke setup. Had to install a new EGR and PCV to pass state inspection last month.

 

try changing the thermostat this worked for me.