Hi Ray
The new book on Chrysler engines (see earlier post) has a few paragraphs on an experimental DOHC head for the Hemi. It was developed in 1964 as a response to the Ford SOHC. When NASCAR outlawed the Ford, Chrysler discontinued the project. If I knew how to post a picture, I would post an engineering drawing. Is there a place on this website where they say how to do it?
By the way, the same book (Written by W. Weertman, who started at Chrysler just after WWII and retired 1987 as chief engineer of engine design) says the the turbine was dropped about 1970 because there was no way to make it fuel efficient.