Pinging

Jimmy,
What kind of timing light are you using. If it is one with the adjuster dial, have a buddy rev the engine for you, slowly increasing it up to about 3200 rpm. Adjust the dial until your timing marks read 0 degrees. Then look on the adjuster dial, wherever it is reading is your total timing. Now rev the engine, slowly bring it up until your timing marks are reading 0 degrees again. The tach should give you the rpm that this happens at. This should be lower than the 3200 you used the first time. Whatever the rpm is, is the all in point of your timing. You should do this with the vacuum advance unplugged. I could be wrong but I don't believe the vacuum advance does much at WOT. I don't even have vacuum advance. Once you get these readings you can make adjustments with springs in the dizzy to get the best combo of timing for your engine. My 360 with 10.5 to 1 compression running 91 octane likes 16 init and 34 total, all in at 2500. That's with a Magnum 280 h comp cam.

Jack