1967 Chevrolet K20 Suburban Engine: 4.8L L6; 1 Bore Gasket; Position: Carburetor To Intake Manifold;. 1967 Chevrolet K20 Suburban Engine: 4.1L L6; 4 -Notch Bypass; 1 Bore Gasket;. 1967 Chevrolet K20 Suburban Engine: 4.8L L6; 4 -Notch Bypass; 1 Bore Gasket; Position: Carburetor To Governor;.