Engine experts, why these notches? (Pics)

[gkz]

On the bottom edge of the cylinder, there's a notch. If you look between the lifter bores, there looks like a scribe mark that is inline with the notches. Are these notches common? My block was checked by dye penetrate/magnaflux to be OK.

 

[clutchdust]

Are you talking about the small notch that lines up with that casting seam that goes in a straight line between the cylinder, across the cam journal to the opposing lifter bore? I don't recall seeing any casting seams that noticeable in the past but I suspect that's all they are. Obviously not clearance notches for stroker or anything of the sort. Just looks like a casting seam to me. If the block checks OK, I don't think I would worry too much about them but you might want to hit them with a grinder just to reduce the chance of a stress riser in the area.

 

[CNC BLOCKS]

Those look like casting lines, Also when adding a stud kit its a good idea to have the block line honed!!