Thanks guys but already thought of those ,would like a definite answer from somebody not a guess. ?? LOL ken ct. Why is it so marked and others ive seen dont have this marking.Its definately factory. There raised letters [not stamped in].
In the 33-34 version of this book on page 3-9 it say this means" High Temp " . Not my info just an observation .Ken, Did you look in the 1935-36 Ford Book by EFV8C/A? I'm thinking I read something in there on this or maybe I'm thinking of a past Fordbarn post that explained this HT marking as well as other markings found on the original aluminum heads. If the info is not in there, I bet Don Rogers would know exactly what the HT means with no guess work. Send him a personal message with your questions and then let us know what you find out.
Thanks Don you beat me to the PM i just sent you. Just disreguard it. I still am confused why were some HT and some were not. ken ct.HT does mean Heat Treated. Some archive drawings have this notation and some don't. There were 3 companies supplying heads and intakes to Ford (Alcoa, Bohn, & National Bronze), so the markings might be a manufacturers preference.