Engine Markings... pls help!!!

Hello mopar friends

can anybody tell me what this markings on this 1970 made engine means?

I mean specially K7 and K4

but maybe al of the numbers...

thx

David

K could be assembly Plant---Toluca is a code K the 7 could be for year, but not positive, what is casting date on your block, does it have 70 casting date.

yes 70 casting, i am searching for a code for overbore...

FW340P31770423;

F - Series (model year) 1970
W - Windsor, Ontario engine assembly plant
340 - 340 cid
P - Premium fuel required
3177 - Final assembly date from the 10,000 day calendar - April 9, 1970
0423 - 423rd engine assembled at this plant on the date above.

The 1970 TSB that covers the engine markings does not mention a "K" at all. You can read it at this link if you like - http://www.hamtramck-historical.com/1970-Dodge-TSB-Index.shtml Drop down to Chapter 25 in the grid & read D70-25-1, there are 8 pages.