4. Now for a little block ID’ing. Here’s an 8BA block, which was the last version, produced from 1949-53. The (removable) water outlets were relocated to the front of the heads; additional cooling passages were also added. The bellhousing is no longer integral (now a bolt-on). Stock displacement was 239 ci; same-era Mercurys were 255 ci, thanks to their 4-inch cranks.