engine code ?

The thrird digit is the vehicle designation, in this case,the "V" stands for Lincoln. The fourth digit is for the division that produced or used the part , E is for engine, Z is parts, there are others that I can't recall. The D0VE-C heads are good ones, just not CJ or PI heads. They do have the smaller chambers ( good for compression) and screw in rocker studs ( but they're the positive stop type) Take them and have the larger CJ/PI valves installed and port them to match CJ intakes and exhaust and they actually flow better than the CJ heads, more akin to the later PI heads.