I have vacuum advance.................... I leave it connected when checking my total .............. And yes total meaning initial+mechanical
Well now you've contradicted yourself................
The thing is..............
1---and only ONE and FIRST and in my book MANDATORY is to first check for absolute certain whether TDC is actually correct. Probably the most accurate and easiest way to do this on an assembled engine is with a piston stop
2---I personally do NOT trust "dial up" timing lights unless I have proved they are accurate. In today's world with Craigslist, garage sales, etc, there is no reason NOT to have a cheap used working "non" dial up light for testing. I much prefer to degree the balancer instead. You do not need to spend a lot of time on this. Once you have your TDC checked as accurate, you can mark the important points on the balancer as needed, 5, 10, 15, 20, 35* 40, 50, 55 is a great plenty. You can easily do this by simply accurately measuring around the balancer with a small tape, and calculate degrees vs circumference.
2---Determine WHAT the mechanical and vacuum curve are that's in the distributor, SEPARATELY from each other. In other words, unhook the vacuum advance until you have charted the amount and rate of the mechanical and then check the vacuum at an RPM which you know won't affect mechanical readings.
3--In rough figures, you probably want somewhere around 34--38 total initial + mechanical, with as much as 50-55 including vacuum at "light throttle" high speed cruise.
At the same time you want plenty of initial. "Crack" seems to like more than me, but what I've run lately is not that "lumpy." My 318 seems fine with about 17 initial.
4---If you think the mechanical is wrong, you need to find out "what the engine likes." You need to establish initial, do so by timing for max RPM or vacuum at idle, going back/ forth and adjusting idle speed, idle mixture and timing, then double check that starter does not kick back when engine is fully warmed.
Once this is done, you need to find out what the engine wants for wide open throttle mechanical only. NO vacuum. This is your 34--38 range. Nowadays, with such "hacks" as headphone knock sensors, wideband O2, etc, you can do this easier, but there is no substitute for a dyno. No, I can't afford 'em, either.
So assuming you have these two extreme points in play, the next thing is to attack the distributor mechanicals so that the advance gives you that range.
5---Springs are last, which control the rate of advance but the wilder the engine, the more advance it can handle quicker. "Back then" I used to run a dual point dist. with NO springs. The points caused enough drag to pull back the advance to start, and right after starting it was pretty much "all in." This too is a matter of trial and error, and there is no easy way without a nice expensive dyno. Pinging at part throttle is a clue. Without a dyno, you are just guessing. One of the G-tech meters or other onboard accelerometer might be of help.
