The valve cover design is a good clue, as Tom noted. Also, if the valve covers are not scalloped at the bottom edge, there is a casting number on the block that will give you a reference. If you post the number here I'm sure we can decode it. Gary H. > The individual I bought it from said that a > previous owner put in a 318. How do I tell if it is a 318 or not and > which 318? ---- 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! '62 to '65 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html.