What I found was the bushings all allowed to much advance for the initial that my engine needed. My engine ran best with 34° total and liked 22° initial. If I set the total timing it wasn't happy at idle and if I set it at idle it had way to much total.
There was a member here that made custom bushings so I bought one and sanded it down to get the right amount of advance. It's been years ago and I can't remember who it was.
Crackedback is who you're looking for. I bought a 10* bushing from him. Works great for my 22 initial and 32 total on the 472 hemi... Or at least I'm somewhat sure that's what his name is?!?!?!?!?!