GM 10124580 Castings
Intake runner volume 245cc
Combustion chamber volume 54cc/65cc
Intake Valve 2.150 dia. x 5.560 length
Exhaust Valve 1.625 dia. x 5.560 length
Intake port opening at gasket 2.1H x 1.335W
Distance from floor to deck at gasket 1.32
Intake min. cross sectional dim. 2.555 sq. in.