Sorry this got kinda long. Alright, I have a carbed 350 in my car, basically EVERYTHING is new on the car. I'll cut to the chase. After changing to shorty plugs and cut to length wires, every once in a while my engine will shudder around idle speeds. I have not found any relevance as to when it does it.

Stuff I have noticed that makes no difference: engine temp, idle speed, variations in base timing, idle mixture, in gear or nuetral.

It is not a constant problem, it will only happen every once in a while. It will do it for maybe a few seconds, usually noticed while backing down the driveway.
Now I would look first at the fact that this problem seemed to start occurring after I swapped plugs and wires.
MY NEW WIRES ARE ROUTED IN A TIGHT BUNDLE from the back of the heads to the dist cap. Could this be it? It isn't missing or having any other symptoms I can notice. I've checked for arcing at night, no obvious damage to wires, caps are tight, etc.