In 66 they only were available in c-bodies and not a high performance version. The 66 440 had the 915 heads but they were small valved, whereas the hp 915 heads, which came out in 67 with the b-body, had larger valves-the horsepower difference between the two were rated 25 hp different 350 versus 375. I have a stack of the 915 close chambered small valve heads, nobody wants them, although, you can install the the larger valves in them. neal zimmerman, eugene oregon ---- Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks! 1962 to 1965 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html and http://www.1962to1965mopar.ornocar.com/general_disclaimer.html.