A couple weeks ago we presented a description of the Orion engine prototype taken from the 1975 book Some Unusual Engines by LJK Seltright. Today we present another tank engine mentioned in that book, the Japanese 10 ZF V-10 air-cooled two-stroke diesel. This is the engine that powers the Japanese Type 74 MBT, producing 750 HP. Compared to western armored vehicles, not much has been published regarding the Japanese Type 74. This is the first detailed description we have found of this particular engine so we thought it was worth sharing.