100s of posts on this subject. It can get complicated too. Those who have figured it all out say total advance or all in should be 34 degrees at 2500 rpm.
18 degrees base can cause more than the 34 total in many distributers. Sprigs in the centrifugal advance can prevent all in by 2500 rpm. Thus altering the travel in centrifugal advance, changing those springs, all those complications. I didn't mention rotor phasing but I'm sure someone will if you persist.
Those of us who don't race and need every bit of horse power set to get a good run with no ping and drive.