John the 781 heads are 118cc they are a open chamber oval port they are a really good head they flow really good, I had a set on my bracket car 433 cid (396 60 over with 454 crank) no big cam 595 lift 294s comp cam and a 850 holly 10 to 1 and it would run mid 11,s
those are good heads keep them they are getting hard to find.