In some endurance and most oval track applications, it is necessary to use a Rev Kit for the lifter to precisely follow the profile of the cam. This safety measure ensures that in the event of pushrod breakage or rocker arm failure, the lifter will not come out of the lifter bore. This could cause a loss of oil pressure and a subsequent engine failure. These Rev Kits come with all necessary springs and buttons. The angle of the spring pockets duplicate the lifter angle in the block. Spring mounts are notched to fit the block where necessary and should require no machine work.