The Stovebolt Site Forums The Shop Area Engine Shop Chevy 235 Block Numbers.

I suspect that the block may be a replacement. The serial numbers as you posted are very different from mine. Did you take them from the flat area just in front of the starter?

Mine are: Engine Code: FI20A (serial number)
F - Flint, MI engine plant
1 = January
20 = 20th
A = regular production engine with 3-speed or overdrive

If you look at mine, the stamp is somewhat uniform. Yours look like they were hand stamped.

I’m sure some of our experts can give you more info.