This roller lifter kit is used on all late model V8 blocks 1986 and newer. These second design lifters are used in late model 350 HO engines and use a higher checkball spring preload. This kit includes 16 of 809-17120735 roller lifters, 8 of 809-12550002 valve lifter guides, one of 809-14101116 valve lifter guide retainers, 4 of 809-24501365 retainer bolts, and 4 of 809-120386 retainer washers. This kit plus pushrod kit 809-12371041 and a roller tappet design camshaft will convert your engine to a roller lifters engine. Use kit items listed above for single service parts.