Not an A-body but it has a 440

Year of the car? You can get a better idea of a cast or forged crank depending on year. Also a 6-pak or a cast crand will have a offset weighted damper versus a forged crank will have a smooth damper. Take the dist. cap off, put a breaker bar/ratchet on the crankshaft nut and turn it back and forth to see how much play is in the timing chain before the distributor moves.