[cobrashoch]

Depends, I've done it both ways on custom engines. Inside the dist. vacumn curves (initial advance) are one of those tuning things you do to set a engine up, along with jetting a carb, and setting a advance curve. When I fire a new one up I use no vacumn and retard the dist. a bit just for safety. After things are going a bit I usially start some of the tuning stuff to bring her in. Most times after things have settled down I end up using the maifold full vacumn because it's typically more consistant on low vac. engines, but you will have to play with springs, programs or such. There are many factors to look at but I typically ask a guy how are you going to use the car/engine, and that determines how it's really done. I know this is no help but that's the way it usially gets done, it's a tuning thing and it depends on the type of engine you have.
cobrashock