The danger from too much spark lead is not the pinging you hear when pulling a grade at part throttle.It's the detonation occurring at wide open throttle when it's hard to hear it over the engine roar.Repeated full throttle detonation breaks pistons,cracks bearing caps,causes crankshaft breakage and of course reduces power.This destruction won't happen from an occasional 10 second full throttle blast but doing it longer and more often can be an issue.
True proper total spark advance is most commonly done on dynometers. Then the basic settings can be transferred to other engines and adjusted slightly for conditions.It can also be done with repeated timed acceleration runs,the drag strip.
I don't believe any simulated situation can give you accurate timing for a real engine,close maybe.
Who here knows the best spark advance curve and maximum degrees for a 235 or 261 Chevy? How about 270 GMC?
