the AAA version. It had a bore of and a stroke of , for a total displacement of . In 1994, a ABV version was introduced in some European countries, with an increased bore of . The V angle between the cylinder banks is 15°, and the compression ratio is 10:1. The crankshaft runs in seven main bearings and the journals are offset 22° to one another, in order to accommodate the offset cylinder placement. This also allows the use of a 120° firing interval between cylinders. The firing order is: 1, 5, 3, 6, 2, 4. The centerlines of the cylinders are offset from the centerline of the crankshaft by . The valve sizes are for the intake and for the exhaust. Since the two 'rows' of pistons and cylinders share a single cylinder head and head gasket, the piston crown (or top surface) is tilted. The engine management system is Bosch Motronic. 24-valve versions A version with four valves per cylinder (for a total of 24 valves) was introduced in 1999. The 24-valve versions use one camshaft for the intake valves of both banks (using rockers to reach the furthest bank) and the other camshaft for the exhaust valves of both banks (again, through the use of rockers). This operating principle is more akin to a double overhead camshaft (DOHC) design, with one camshaft for intake valves, and one for exhaust valves. History The 1922-1976 Lancia V4 engine was the first narrow angle V engine to be used in a motor vehicle. The first versions of the VR6 engine were introduced in the 1991 Volkswagen Passat B3 sedan and Volkswagen Corrado coupe. A AAA version producing was used in most Passat models and in the North American version of the Corrado. A ABV version producing was used in the Passat Syncro model and the European version of the Corrado. Both versions used 2 valves per cylinder. Usage of the VR6 engine spread to the Volkswagen Golf Mk3 2.8 VR6 and Volkswagen Vento/Jetta (A3) 2.8 VR6 models in 1992. The 2.8 litre version was also used in the 1996-2003 Mercedes-Benz Vito (W638) commercial vans, where it was designated as 'M104.900'. In 1997, the VR5 engine was introduced, based on the VR6 engine. An AQP/AUE version with 4 valves per cylinder was introduced in 2000. This engine produced , and mostly replaced the 2 valve engines, except for in North