Avenger aluminum Cnc cylinder heads fully assembled, 385cc intake ports, 123cc combustion chamber, Rev 2.30 x 1.90 stainless steel valves, Manley Nextek 1.625" dual valve springs w/ max. .850 lift for solid roller camshaft, heads flow 450 @ .850 intake / 358 @ .850 exhaust, Manley titanium retainers, rectangle port, 24 degree head, race radius valve job, bronze valve guides, stock intake & raised .375" exhaust port locations, sold as pair, new