The Performance Build Center in Wixom, Michigan, specializes in producing low-volume engines for GM's premier vehicles with a combination of personal attention and technological prowess. The 38 employees at the plant, 25 of whom are skilled builders, can produce 45 LS9s a week. The process starts here, with these just-delivered blocks and cranks. They're supposed to be clean upon arrival, but GM Powertrain pressure-washes them again just to make sure. Each builder carefully examines his block before assembly begins, and can reject it if he finds something he doesn't like.