Originally Posted by GREGGPENN
Block numbers were even the same! IIRC, the casting simple says "638" on the side of the block.
You're referring to the designation I presume (like L98)?
The casting # is just that , a casting #.
Has no bearing on what config ( designation ) the engine left the factory as.
The fabled "010" block was used for everything from 165 Hp truck engines to 370 Hp LT1 Vette engines
but every hot rodder swears his block came from a '70 LT1 Vette to the point where there are
more "Vette" 010 blocks running around today than ever left the factory clothed in fiberglass