The inliners.org website has a large database of inline Chevy and GMC casting numbers. Also look for the casting date near the starter, lower rear block on passenger side. Date code starts with a letter that indicates month, A=Jan, B=Feb, etc. then a one or two digit number for the day of the month then another number for the year. Ex: E 12 9 would be May 12, 1949 for a 216 (or Loadmaster 235 Hi-Torque). A late model 235 or 261 it could mean May 12, 1959. Good luck.


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