versions of the M42, BMW engineered a dual length intake manifold (called "DISA" by BMW) Versions M42B18 The M42B18 has a displacement of , which is achieved through a bore of and a stroke of . Versions equipped with a catalytic converter produce and . and meet the Euro 2 emissions standard. Applications: 1989–1991 E30 318is 1990–1992 E30 318i (only North American models) 1992–1995 E36 318i (only North American and South African models) 1991–1995 E36 318is 1994–1995 E36 318ti S42B20 The racing version of the M42 engine is called the S42 and was used in BMW's 320 4-door touring car, participating in the German Super Tourenwagen Cup. Compared with the M42, the S42 has individual throttle bodies, the displacement increased to , two fuel injectors per cylinder, an increased compression ratio and a different cylinder head. The valve cover and airbox were made from carbon fiber and the lubrication system used a dry sump. In 1994, the initial version of the S42B20 engine produced . Outputs gradually increased to for the final version in 1997. Timing system revisions The earliest versions of the M42 developed problems with the camshaft chain drive. The hydraulic tensioner, chain guides, idler wheel and rear lower chain case were updated to resolve wear problems experienced in the early versions of the M42. The updated cam chain tensioner is shared with that of the later M44 engine. In September 1993, BMW redesigned the M42's timing chain guide rails, replacing the occasionally troublesome lower idler gear with a curved nylon guide rail. The idler gear's retaining bolt could break away from the timing case, often taking a chunk of alloy timing case with it. Recalls Early models of the M42 experienced failures of a profile gasket sealing the lower cam chain case to the underside of the cylinder head. This gasket seals the primary coolant passage within the timing chain case. A significant failure would thus discharge pressurized steam and hot coolant into the timing chain case. In many cases this coolant rapidly contaminates the motor oil in the sump, causing main bearing failure. BMW updated the profile gasket material and instituted a program to repair motors under warranty. In extreme cases, the aluminum mating surfaces in the head and chain case would corrode. See also BMW List of BMW engines References M42 Straight-four engines Gasoline engines by model