Vacume Problem?

It sonds like your vacume pot is adding to much advance. you need to adjust it. There is an allan screw where the vacume hose goes on that you can turn to + or - The advance in it. You may also need a working timeing light. Setting the timing by sound is not very accurate. I have tryed it. then I put a light on it to check it and it was way off of where I wanted to be.