340 HEADS CASTING DATES???

[Scatpack]

I forgot how to decode casting date for 340 j heads,any webistes?
they are 2860 and 2870
thanks

[srpntlair1]

best I could find original valves on true J heads were 2.02 in 1971  1.88 in 1972

[Musicman]

You can check the Tools/Reference section at http://mymopar.com

Reference from another site:
For 1971 and 1972, 340 and 360 engines were equipped with 3418915 heads, so-called "J" heads, because of the cast-in J in three locations (backwards in one place) on each head. These were either equipped with 1.88 inch/1.60 inch valves, or 2.02 inch/1.60 inch valves, and have "open" chambers with volumes of 65-73 cc.

[69CoronetRT]

I forgot how to decode casting date for 340 j heads,any webistes?
they are 2860 and 2870
thanks

286th and 287th day of 1970