Partial VIN #2B391090 casting #on side of block 2780930-340-5 number under drivers side head 80119 and 9-28-71 is cast into it also. I guess this makes it a 72 model block but the J heads have 2.02 valves and have been milled so compression is not a problem. This engine went 12.1 in my 73 Dart and has been freshened since then.
