B or RB?

[4x4HEMIrig]

I found some casting numbers on the block in my Chally, I can't tell if it starts with a "B" or an "R" ...

      C383
BMS38961
      4  14

AND

     C383
RMS38961
      4  14

What do they mean?

[Strawdawg]

Looks like a '67 casting from the C......and a 383 that was cast on April 14 to me.   Don't know what the middle number is.

[4x4HEMIrig]

Cool! Thanks! Another guy I was talking to over on the Hemi Truck Club forum says it's a "B" block motor.

[dodj]

A 383 is a 'B' block
I think the middle number is a production sequence number.

[Strawdawg]

Cool! Thanks! Another guy I was talking to over on the Hemi Truck Club forum says it's a "B" block motor.

yep

[4x4HEMIrig]

Thanks guys.

[Chryco Psycho]

there actually is a RB 383 block used in the late 50s but yours is not a 50s block