How to identify my 4 speed transmission

[Kern Dog]

I READ ON THE INTERNET...
Come on, man! The 340 was only installed in the A body cars in it's first 2 years, 1968 and 1969. In 1970, that expanded to include the E body cars. NO B body car was equipped with the 340 until 1971. The 340 went out of production with the end of the 1973 model year. NO 340s were installed in any factory built 1974 cars. THe 340 was a shorter stroke engine that made it's power at higher rpms, exactly opposite of how the OEMs were heading in the 70s. The longer stroke 360 became the essential replacement. In 1974, the 360 4 barrel was rated at 245 HP, 5 HP more than the 72-73 340 engine.
If the 340 was in the 74 Charger, someone changed out the original engine and slipped it in AFTER the car left the assembly line. Maybe it was a dealer replacement?

[John_Kunkel]

OP ID'ed it as a 340 by "the numbers on the block", what numbers where?

[Loa]

The block is stamped with HM 340 R, so a 72 engine in a 74 car. (Unless the net is wrong on the meaning of the "H".)

By the way, when people write "from what I could find on the net", it means that they're not sure, that's the best info they could find so far. When that info turns out to be wrong, a simple "What you read online was wrong." is perfectly acceptable.

I remembered reading that some 74s had 340 before they switched to the 360. But maybe that was for the 73s. I'm not sure.