I finally got close enough to read the stamp on the block and I can't figure out what the numbers mean. Near as I can see, its 430119909. From what I've read, it should start with a 3 and have a letter indicating the plant. Its deifinitely an Olds-block casting is 395558 with a big 2 at the end. Oil tube is stamped 332335. I have no history on this motor, so could be pieces from another engine, but I would really like to know the year of the block. Can anyone help?

 

Somethings not right with that stamping. The casting is a 350 for sure though.
It should be something like 30M119909. 3 being Olds, 0 being the year (1970) M is the assembly plant where the car was assembled and the last six match the last 6 of the car it was installed in.

 

Post the 9 digit code from under the #1 spark plug. From the oil fill tube #, it appears to be from 1973. What heads are on it? What # is on the carb. Where did the 43... number come from? Lots of questions asked, to answer the original.

 

The heads are #8, which also would indicate a '73. No idea why the block number starts with a 4, and as you said should have a letter indicating plant (those numbers are on the pad beneath the #1 cylinder). I may be misreading it, but I checked it pretty good.

 

Well, this is weird. Did you pull the motor from a car, or did you just get a block? The "4" would indicate Buick Division. In later years, when GM mixed and matched engines and divisions, it would have been possible to find an Olds block in a Buick car and the VIN derivative would have started with a 4. In 1973, that was not the case. The "3" of course indicates 1973, which is also consistent with the 395558 block casting. The 3 could also indicate 1983, but that wouldn't have been a 350 block.

Are you sure the third character is an "O"? In 1973 there was no "O" code assembly plant. The closest characters would have been "C" (South Gate, CA), "G" (Framingham, MA), or "Q" (Detroit, MI).

B-body cars were built at South Gate in 1973, so it's possible that this motor came from there, and that the VIN derivative was mis-stamped at assembly.

 

I think I need to clean it up a bit better and take another look. This was read with the motor in the car-I had the inner fender off which gave me pretty good access but maybe not good enough. Thanks for the input

 

Nothing is written in stone. I have a spare 1973 455 engine with all 1973 castings including serial number, intake, etc. and the block says 396021 F. It really should say 396021 FA according to all the literature.