The lifter bores in a SBF roller block are cast taller than the early flat tappet blocks. The tops of the bores are machined flat and the dogbones are held down against it with a spider. The spider is held to the lifter valley with two small bolts.

You can add a roller cam to a non-roller block by using one of the roller lifter sets with the link bars. Another option is to use a roller retrofit kit but these use a small base circle cam to make up for the shorter lifter boors.



--Patrick