uses a guide 54 which mounts to the engine block 24 the lifter guide 54 includes a main flat guide portion 55 sized to span the distance between two adjacent lifter bores 22 as seen in fig2 and 11 to physically secure the lifter guide 54 to the top of the engine block 24 a fastener 56 typically a threaded type fastener is placed through a slot 58 in a tab portion 59 projecting from an intermediate position along the length of the main flat guide portion 55 away from the bores 22 the lifter guide 54 also has two small crescent shaped portions 60 that depend from the flat portion 55 out of the plane thereof for extending into the lifter bores 22 as shown in fig1 and 11 the curvature of curved surface 60 a the crescent shaped portion 60 mates with the curvature of the lifter bore 22 thus the curved surface 60 a and the guide member portion 55 form a tight fitting shoulder 61 that securely engages against the corner 63 at the junction of the upper end of the bore 22 and the top of the engine block in this manner as the guide member encounters torquing forces that want to twist it out of position and loosen its connection to the block the tight mating engagement between the shoulder 61 and corner will resist these forces to keep the guide member in proper position for guiding and resisting rotation of the lifter body as it reciprocates in the.