Cylinder Head Specifications: Combustion chamber volume: 64cc; Intake runner volume: 210cc; Exhaust runner volume: 75cc; Intake valve diameter: 2. 08"; Exhaust valve diameter: 1. 60"; Valve stem diameter: 11/32"; Valve guides: Manganese Bronze; Deck thickness: 9/16"; Valve spring diameter: 1. 46"; Valve spring maximum lift: . 575"(5085) / . 650"(5087); Rocker stud: 3/8"; Guide plate: Hardened steel; Pushrod diameter: 5/16"; Valve angle: 23°; Exhaust port location: N/A; Spark plug fitment: 14mm x . 750 reach, gasket seat * Recommended spark plugs are Champion RC12YC or equivalent 14mm x 3/4" reach with flat gasket seat. Requires hardened pushrods. Edelbrock recommends Fel-Pro #1206 intake gaskets for use with E-210 cylinder heads.