At present you may (probably) not getting any advance at idle just what you set to. It takes more RPM's to start stretching the stiff springs to get some of that 14 mechanical advance.

But put lighter springs in and idle rpm should be enough to allow some stretch and some mechanical advance. so say if you put the lightest springs in that came with your dizzy 950 rpm may allow dizzy to advance lets say 8 deg so that will give you 19 + 8 = 27 advance at 950 instead of it sitting at 19 total in both cases is still 33.

so one light spring may do it maybe needs too it's trial and error.

But as i said you can at idle turn dizzy till you get say 27 then mess with idle if it's good then tailor your advance springs to get you there after turning dizzy back to where it was.