Tech Tips folks. About 1/2 way down in the Engine Tech Tips there is a thread by Barry Weeks that spells it all out.ðŸ›
Barry Week's write-up is quite good.
But, I think it does not discuss the oddities of "Captain bars" on some 235 engines (in 1953 and 1954), as posted by 1953 panel in the second post, above.
Engine Serial Numbers are good, but they can be changed/missing.
The block/head casting codes definitively ID 235 vs 261, and the block/head date casting codes definitively ID the years.
Post those codes if you want to know for-certain what you have.
