The Mitsubishi 4B1 engine is a range of all-alloy straight-4 engines built at Mitsubishi's Japanese "World Engine" powertrain plant in Shiga on the basis of the Global Engine Manufacturing Alliance (GEMA). Although the basic designs of the various engines are the same, their exact specifications are individually tailored for each partner (Chrysler, Mitsubishi, and Hyundai). The cylinder block and other basic structural parts of the engine were jointly developed by the GEMA companies, but the intake and exhaust manifolds, the cylinder head’s intake and exhaust ports, and other elements related to engine tuning were independently developed by Mitsubishi.