was replaced by a more advanced Gleason-licensed Torsen—or "Sensitork" in Maserati parlance. The engine was an evolution of Maserati's own all-aluminium, quad overhead cam V8, fed by four Weber carburetors. The automatic transmission used was a three-speed Chrysler A727 "Torqueflite" gearbox. The manual gearboxes are ZF S5 five speed units. When leaving the factory all the cars were originally fitted with Pirelli Cinturato 205VR15 tyres (CN72). Coachbuilders Milanese coachbuilder Carrozzeria Pavesi outfitted several armoured Quattroportes during the 1980s. One of them, a 1983 Blu Sera example nicknamed Calliope, was notably used by President of the Italian Republic Sandro Pertini as the official state car during his tenure. Autocostruzioni SD of Turinese coachbuilder Salvatore Diomante also offered a 65 cm longer limousine version, fully equipped with white leather, "abundant burr walnut", mini-bar, video cassette player and many other necessities. The price of the Diomante limousine at its introduction in 1986 was 210 million lire. Quattroporte IV (AM337 1994–2001) The fourth generation of the Quattroporte (Tipo AM337) was manufactured from 1994 to 2001 and was the first car to be produced under the Fiat ownership after Alejandro de Tomaso sold his entire holding to the Italian marque in 1993. It was built on an evolved and stretched version of the Biturbo saloon's architecture, and used the twin-turbocharged V6 and later the new AM578 V8 engine from the Shamal flagship grand tourer. For this reason, the car retained very compact exterior dimensions, and is smaller than any of its predecessors and successors. As the designer's signature angular rear wheel arches gave away, the wedge-shaped aerodynamic () body was penned by Marcello Gandini. History The world première of the fourth generation of the Quattroporte took place at the April 1994 Turin Motor Show and the car went on sale towards the end of the year. Initially the Quattroporte was powered by the twin-turbocharged, 24-valve V6 engines from the Ghibli. For export markets there was a 2.8-litre unit, generating a maximum power output of and allowing the car to attain a claimed top speed of . As local taxation strongly penalised cars over two-litre in displacement, Italian buyers were offered a 2.0 L version, which developed a little more power () but less torque than the 2.8-litre version; on the home market, the 2.8 was not offered until a year after its introduction. The cabin was fully upholstered in Connolly leather and trimmed in elm