Our auto shop instructor, who was retirement age our first year with him always said "give one all the advance it can stand, without spark knock or lugging the starter". Direct quote. I've found that works very well and 9 time out of ten it ends up right where all the calculations with a timing light and vacuum gauge will tell you. Other than "possibly" limiting total timing, that's really all you need to do. Now of course, racing for points or money, you're gonna wanna pull the tuning tools out, but you're still gonna be close the old way.
