After changing cutting heads, Demirjian then removed the rest of the cylinder wall material. Even though a lot of material is removed, the new sleeves are heavier and an MID-sleeved block will end up around 6 pounds heavier than a factory block. As you can see, quite a bit of material is removed in this process. It’s easy to see how someone inexperienced with this process could end up ruining a block. Demirjian then put the block on a stress relief table for an hour, a step that he feels is critical to ending up with a reliable finished product.