Excessive initial timing just causes more turning resistance that makes the starter work more, potentially shortening it's life. Keeping the Initial timing around around 10-12 or so reduces that load on the starter. Then adjust the mechanical advance to give the total that engine wants at wide open throttle under load, like full throttle acceleration. This is where the FBO limiter plates come in handy on stock style distributors. Of course the springs and weights get adjusted for the curve from initial up to total, and at what RPM. Finally, the vacuum advance should be connected to manifold vacuum so that as soon as the engine starts the vacuum pulls in more idle and low RPM timing that the engine needs to run best and get good fuel economy.
