I have a stock 350 carbed motor /w t350. For a while now Iv had a miss after it has warmed up. Timing is probably around 16* and locks out at 35*. Its very odd because, if I retard the timing anywhere passed that I have a bad hesitation if I romp on it until about 4k rpms and then it smooths out. However, if I retard the timing to around 12*, after its warm i wont have a miss at idle. Iv re adjusted the valves, removed the floats from the carb n cleaned 'em out with the jets and secondaries, checked for vacuum leaks, it has new plugs n wires gapped correctly. Im not sure if its in the dizzy or where else to look.