The Toyota GZ engine is used as the powerplant for what  large four-door limousine produced mainly for the Japanese market?
Toyota Century The Toyota Century (Japanese: トヨタ・センチュリー) is a large four-door limousine produced mainly for the Japanese market, serving as Toyota's flagship car within Japan; whilst globally the unrelated Lexus LS series is Toyota's flagship luxury model outside Japan. Production of the Century began in 1967 and the model received only minor changes until a redesign in 1997. The Century derived its name from the 100th birthday of Sakichi Toyoda, the founder of Toyota Industries. The Century was available with only a V8 engine, the third Japanese built sedan post-war, at its introduction in 1967 until a major redesign in 1997, and is now only available with a Toyota built V12, an engine unique to the Century. Although the Century is a premium, full size luxury sedan, it is not available at Japanese Lexus dealerships; it can only be purchased at specifically identified "Toyota Store" locations. The logo used throughout is called the "Hō-ō 鳳凰" or "Fushichō" from Asian mythology, representing the Imperial House of Japan.
Kia Optima The Kia Optima is a mid-sized 4-door sedan manufactured by Kia Motors since 2000 and marketed globally through various nameplates. The Kia Optima mainly competes against cars such as Chevrolet's Malibu, Buick's Regal, Honda's Accord, Mitsubishi's Lancer, Nissan's Altima, Toyota's Camry and Volkswagen's Passat. First generation cars were mostly marketed as the Optima, although the Kia Magentis name was used in Europe and Canada when sales began there in 2002. For the second generation models, Kia used the Kia Lotze & Kia K5 name for the South Korean market, and the Magentis name globally, except in the United States, Canada, and Malaysia where the Optima name was retained. The Optima name is now going to be used for all markets except China, where they will also use the South Korean market name.