Easy now, lol. Here is the thing. Custom settings are necessary no ifs ands or buts. The gasoline that was sold when the shop manuals were written is not the fuel we have available to us now, i.e., the unleaded, alcohol infused, additive laden stuff we are calling gas. Winter blend, summer blend, fall blend. It flashes off at different points, evaporates its volatiles more easily, hygroscopic water absorption at room temperatures, all kinds of stuff. All of those factors now have to be taken into consideration with these old cars. That is why it is so very important that all of the ignition periphery be pretty spot on in order to dial in the motor to run its best and get some consistency. Thus, the mechanical advance must be pretty spot on. That means not just working, but working as it should. My example above was to show you that I could get to the max mechanical advance, but it would not come in when it was supposed to. At that point, there is no way to accurately time the motor for optimum running. If you have the same issue, and its not uncommon with these distributors at near 60 years and older, neither the ping method nor the vacuum method, nor the dial back light method or any other method will get you any consistency. So, you need to first sort out the specifications. When I get home tonight I will look up my Sun and AEA specification charts for your 62 motor and see where the mechanical advance starts, intermediate and full are supposed to be. Set your motor at TDC, and using an analog dial back light, confirm whether the mechanical advance is working correctly within specification at the appropriate rpm ranges. If its way off, then you need to address that first. If its within specification, start advancing in 2 degree increments until you hit the point where the motor is running smoothly and not pinging when you put a load on. See where that is.
As Jerry noted, its usually, but not always, in the 5-8 degree BTDC, depending on the fuel you are running, the altitude you are at, and the condition of the distributor. Mine ended up at 8 degrees but I am gonna play with it some more this season. You may very well end up with something less or more then what I am running. I know that quite a few use the vacuum method. I myself do not care for that method as every time I try it I end up with total timing that is too much which messes with all kinds of things, idle quality, drivability. Same for the ping method. Lots use it with good results. I have not had good results. No opinion on those methods one way of the other, just my own way of approaching timing on these motors. I have been at this since I was 16 with these old style motors, 41 years now, so I tend to stick what works for me.
Jerry is quite correct, too much advance is just as power robbing as being retarded (and I am saying that in the politically correct mechanic speak, lol) notwithstanding that the motor is seemingly running fine and not pinging. So choose a method, timing light, ping or vacuum, stick with that method, confirm the distributor function and sort out where your motor likes to be with the fuel you are running. Happy tinkering.
