Other blocks do not have these provisions and are not easily adapted to a roller cam, this requires you use a flat tappet cam or a retrofit roller kit. If drilled then tapping them isn't much of a problem. If these are present they may be drilled or drilled and tapped. If it is a roller block casting, it will have the bosses for the cam thrust plate inside the timing case, it will have the raised lifter blocks, and it will have the 3 bosses that retain the spider that posiitons the alignment bars which hold pairs of lifters in proper orientation to the cam. Click to expand.You need to check the block casting number to see if it is potentailly a roller cam block or not.
