The valve cover is attached with 2 bolts and the motor has the long pan - definitely a 216. The 3 letter prefix (ECA) is what is bugging me. Also the next to last character is an "I" - not a "one". Can't find a listing for this motor. There was one reference to prefix "AEC" for a 1947 216 on the Inliners site. Stumped!
BW