notcing the block

What does it mean when the rods or notching or to get the block notched?

when people do this, its so they can run larger rods/pistons so they have enough clearence for em.

Ok thanks but are they like chizzeling or shaving part of the block?

im not sure how its done, but id figure they take a chisel to it, then smooth the edges.

well sb chevy guys do it alot when they stoke to 383 and then they just use a carbide bit and a die grinder