i used to run a tq on my former 340 in a dart hangten. ran 12.70s through the mufflers. i always ran it with stock jetting on the primaries and concentrated my efforts on the accelerator pump and secondary circuits. i used a shooter drilled to .028 in. and moved the acc. rod in the hole closest to the center of the carb on the lever for more pump shot. it allowed me to set the trap door tension to only 1 1/2 turns without bogging on the leave. i used .815 in. on the trap door opening with .156 secondary jets (drilled). i think yours is too rich at wide open throttle probably because your trap door is closed too much. something to try. by the way, mine was the small primary bore size ( 1 3/8) .