Poor idling when cold plus misfire

[Rocky]

Starts fine when cold and hot, but pretty much refuses to idle when cold unless the engine is revved a bit. Doing alot of left foot braking so my right can keep the engine revving. As it warms up it feels like a misfire. But once warm, it runs well.
3.9 Serp V8.
timing is good, coils been changed...
Thoughts?

 

[Rocky]

Just to add, in todays wet weather the misfire was more pronounced and continued even when warm. One of the things I haven't changed are the spark plug wires....

 

[Roving Beetle]

Do the wires and plugs.

Wait till evening so it's dark out and open the hood. Use a spray bottle to mist a fine spray of water over and around the wires and coils - I bet you have a good light show going on!!

 

[Rocky]

Replaced the spark plug wires and instant obvious improvement. Going to run in current configuration for a few days to test and prove the change before taking the next step and replacing the coil to dizzy.