I've never seen a C6AE-L, had almost every other FE head. In 66 they made some different stuff for sure. High and low exhaust ports, short and tall intake ports and Thermactor and non-Thermactor. I guess every combination. Are the -L's maybe tall intake ports and low exhaust?
OK, here's the story. About 20 years ago, when people were jumping off bridges because the Millenium date/time change was going to freeze up all our technology and kill humanity, I did the logical thing and headed to the junkyard, in this case a one-man, part-time biz. This was around the time the C6-R head was starting to bask in the limelight as a CJ alternative. So I came across a '66 Merc with a dirty 390. Scraping off the driver's head, I saw that it was indeed an R head. Had to have. The owner said a couple hundred for the pair, including his labor to remove! Hey, better him than me.
So I meandered around some more and tripped over a big pile of FE's, mostly 50's and early 60's. Nothing shouted out to me as more than generic, so I continued on and got back to the office. There were both cylinder heads. An R and an L. Yikes! My mistake on not checking the other head, ASSuming it would be the same. Argh. Had the port sizes be the same, I might not have even checked the casting numbers. But side-by-side, the intakes on the R were tall, the L's were short. The exhausts on the R were short, the L's were tall. Somewhere along the line, one head got changed out with a total mismatch. I have no idea which was the original. I laughed over the possibility that Ford might have built this on the assembly line.
Anyway, I paid the man, and left. So now I have one odd R head in the pile of R heads, and this one L piece that nobody has seen. In the old forum, there is an old post from somebody with a pair who wanted to know what he had. True to form, Royce Peterson told him in that he was mistaken, and if he cleaned the heads properly the "L" would prove to be something else. Nope, Royce was wrong, as usual. Had that thread not predated my infamous disruption of the site, I would have chimed in.
You would think that, alphabetically, the L head would still have tall ports like the R, but no. Its scarcity speaks for the probable lack of design integrity, but why it was used at all remains a mystery. There are verified C6-J and C6-U castings out there. There are rumors of C6-A's, but I've never seen anything alphabetically before the J. R castings were supposedly used for x months into the '67 production year, when they were eventually supplanted by the C7-A, a somewhat questionable move. At some point I guess I could see how close the L is to a later head.
So that's it! The L head: Ultra rare and worth $5,000? Or, worth 10 bucks as a wall-mount curiosity. You decide.
