I have a 454 block that has an unknown history, long story. Anyway casting code 361959 and date code I26 78. All that makes sense. On the left front pad is C9F127270. I am absolutely sure that is the only thing on that pad. Additionally, directly above the camshaft is another pad with the code T10181RR. Is it possible that the traditional location is just the last 9 digits of the VIN, and the location above the camshaft is actually the number containing the suffix code. If that's true, What's an "RR" suffix code.

I'd appreciate any insights. Thanks!

C=Chevy truck
9=1979 model year
F=Flint plant
127270= last 6 of VIN of truck.
Could the engine code actually be T1018 (October 18 build date) TRR instead of 1RR?
Not sure what year they started using numbers in the engine code, but elcamino will probably be along with more info soon.

361959 1973-85 454 car & truck

Thank you very much. TRR makes sense based on casting and date info

TRR 1979 Truck 454 205 400 LF-8 VIN S, 10, 20

Check ou this web site too.
http://www.mortec.com/bbc.htm