small block cylinder heads
cc's / port volume / size / flow
1966 - 1967 {273} casting #2658920
heart-shaped combustion chamber
factory cc level..........................62.0 to 65.5 cc's
recommended minimum cc's......57.3 cc's
intake port gasket size...............1.05" x 2.07"
exhaust port gasket size.............1.14" x 1.59"
intake valve................................1.78"
exhaust valve..............................1.50"
intake bowl size.........................1.53" {86% of valve}
intake port.................................125 cc
exhaust port...............................61 cc
intake flow...............................158 CFM @ .450" Lift.........160 CFM @ .500" Lift
exhaust flow............................107 CFM @ .450" Lift.........109 CFM @ .500" Lift
intake-to-exhaust flow.....................67.4%................................67.9%.............
