understanding the engine numbers

Posted by David Grubbs On 2014/11/22 17:03:08

My 39 120 has a 282 engine with a production date of 2-1-39. That's easy enough to understand - Feb 1, 1939. On the front of the engine, drivers side, the motor number is B312862A. On the 1940 120's, the B prefix meant that the car had a Borg and Beck clutch, according to Jim Hollingsworth's book. However, I have no idea what it meant in 1939. Ditto for the A suffix. Any ideas out there?