for what it is worth, I agree on a street engine an advance curve is what you want to make it driveable. I approach it this way, I use an engine program, that among other things will calculate an advance curve for the engine combination that I have. It also calculates what rpm ranges detonation will be a problem. So if you don't have access to a distributor machine, the best way is to have a helper raise the rpm in 200 or so increments, use an adjustable timing light, note the timing on some graph paper and connect the dots. If you are using a vacuum advance I like one of those hand pumps with a gauge to see what the advance unit does. Then I change springs or what ever method the distributor uses to try and make my graph match the computer program recommendations. It usually is close. Then fine tune from there.