I was not taking my vacuum into consideration with my total so Im running 16* mechanical, which gets me my 34* total. My vacuum I honestly cant tell you as I've never really paid attention and when I do run my RPM's up my marks on my crank run out, but Im guessing Im somewhere in the 50's when my vacuum is being used.
34° total makes you light and not using the fuel like you should. Vacuum advance falls out under heavy throttle (vacuum drops) which makes you even lighter. You need a better advance curve to get the power and fuel efficiency you should have.
What RPM does your mechanical advance start and then go all in?