Confused Sudden Performance

i had something similar happen in my 65 plymouth with a 6... i was just driving along and all of a sudden it just took off lol... got to the next light and it was idling high... then went to take off and it was a dog... drove a bit and it took off again...

well the dizzy hold down came loose and the dizzy was spinning around so it was adv/retarding on its own lol...