Factory-Painted Block Letters

[69B7RR]

Doing a refresh on my ‘69 HP 383. Noticed faint painted lettering on the sides of the block ranging from A, B and C. The C could possibly be a D. The left side was too faint to outline. The letters appear to have been applied to the bare block prior to the engine paint. Does anyone know what, if anything they signify-possibly bore/piston size after machining?

 

[turbine68rt]

The letters denoted the final bore size after machining so the assemblers knew which size pistons to use respectively.

 

[69B7RR]

The letters denoted the final bore size after machining so the assemblers knew which size pistons to use respectively.

Thanks for the info & taking the time to respond. By chance, do u happen to know what the respective bore sizes the letters represented?

 

[turbine68rt]

 

[69B7RR]

View attachment 1762642

Thanks again for the info. Next time I’m in PA, I’m gonna look you up & buy you a beer. If you don’t mind me asking, where is this info from?