Nope. Those are LAX heads drilled for stud mounted rocker arms, with the stud girdle mounted to the head bolts and rocker shaft pedestals. Single 4-bbl, 423ci/360 on pump gas that made 474 lb-ft @ 3,000 rpm, 574 lb-ft @ 5,100 rpm, 595 hp @ 5,600 rpm and 629 hp @ 6,400 rpm where we shut it off. Toaster IQ52 and his son's magic. Are we having fun yet Rosey?
