The Mercedes-Benz M112 engine is a gasoline-fueled, 4-stroke, spark-ignition, internal-combustion automobile piston V6 engine family used in the 2000s. Introduced in 1996, it was the first gasoline V6 engine ever built by Mercedes. A short time later the related M113 V8 was introduced.

All are built in Bad Cannstatt, Germany, except the supercharged C 32 AMG and SLK 32 AMG, assembled in Affalterbach, Germany.

All M112 engines have silicon/aluminum (Alusil) engine blocks with a 90° vee angle. The aluminum SOHC cylinder heads have 3 valves per cylinder. All use sequential fuel injection with two spark plugs per cylinder. All have forged steel connecting rods, a one-piece cast camshaft, iron-coated aluminum pistons and a magnesium intake manifold. To deal with the vibration problems of a 90 degree V6, a balancer shaft was installed in the engine block between the cylinder banks. This essentially eliminated first and second order vibration problems (see engine balance). A dual-length Variable Length Intake Manifold is fitted to optimise engine flexibility.

These engines, along with the V8 (M113) variant, are often regarded as being the most reliable Mercedes-Benz engines of their era.

E24

The E24 is a version. Bore and stroke is . The engine produces at 5900 rpm and of torque between 3000 and 5500 rpm. The compression ratio is 10.0:1.

Applications:

  • M112.910: 1996–2000 C 240 (W202)
  • M112.911: 1996–2000 E 240 (W210)

E26

The E26 is a version. Bore and stroke is . Output is ECE at 5,500 rpm of torque at 4,500 rpm in all applications except in the 2003-2005 W211 E-Class where power rose to . The compression ratio is raised to 10.5:1.

Applications:

M112.912:

  • 1999–2005 C 240 (W203)
  • 2001–2005 CLK 240 (C209)

M112.914:

  • 1999–2002 E 240 (W210)

M112.916:

  • 2002–2005 C 240 4MATIC (W203)

M112.917:

  • 2001–2005 E 240 (W211)

M112.950:

  • 2000–2001 C 240 (S202)

E28

The E28 is a version. Bore and stroke is . It produces (W220 S280, R129 SL280 and W210 E280) or (W202 C280) at 5,700 rpm and of torque between 3,000 and 5,000 rpm. The compression ratio is 10.0:1.

Applications:

  • M112.920: 1996–2000 C 280 (W202)
  • M112.921: 1996–2002 E 280 (W210)
  • M112.922: 1997–2005 S 280 (W220)
  • M112.923: 1997–2001 SL 280 (R129)

E32

thumb|right|Chrysler Crossfire view of engine compartment

The E32 is a version. Bore remains at but the engine is stroked to . Output is 215-224 bhp ECE at 5,700 rpm (depending on model) with of torque at 3,000-4,800 rpm. The compression ratio is 10.0:1. It has fracture-split forged steel connecting rods.

Applications:

  • M112.940: 1996–2002 CLK 320 (C208)
  • M112.941: 1998–2003 E 320 (W210)
  • M112.942: 1998–2003 ML 320 (W163)
  • M112.943: 1998–2001 SL 320 (R129)
  • M112.944: 1998–2002 S 320 (W220)
  • M112.945: 1997–2006 G 320 (W463)
  • M112.946: 2000–2005 C 320 (W203) & C 320 SportCoupé (CL203)
  • M112.947: 2000–2003 SLK 320 (R170)
  • M112.949: 2002–2005 E 320 (W211)
  • M112.951: 2003–2015 Viano 3.0/Vito 119 (W639)
  • M112.953: 2002–2005 C 320 4MATIC (W203)
  • M112.954: 2003–2004 E 320 4MATIC (W211)
  • M112.955: 2002–2005 CLK 320 (C209)
  • 2004–2008 Chrysler Crossfire

E32 ML

thumb|250x250px|Supercharged C 32 AMG/SLK 32 AMG engine

The E32 Kompressor is a special version of the , fitted with a helical Twin-screw type supercharger. The supercharger was developed in conjunction with IHI and features Teflon-coated rotors producing overall boost of with the factory 74mm clutch-activated pulley. A water-to-air intercooler made by Garrett is fitted beneath the supercharger inside the V, with a 0.8L Heat-Exchanger mounted under the bumper run by an electric water pump. Output is ECE at 6,100 rpm with of torque at 3,000-4,600 rpm. The compression ratio is 9.0:1.

Applications:

  • M112.960: 2000–2004 SLK 32 AMG (R170)
  • M112.961: 2000–2004 C 32 AMG (W203) & C 32 AMG SportCoupé (CL203)
  • 2002 A 32K AMG
  • 2005–2006 Chrysler Crossfire SRT-6

E37

The E37 is a version. It retains the stroke of the E32 but is bored to . Output is ECE at 5,750 rpm with of torque at 3,000-4,500 rpm. The compression ratio is 10.0:1.

Applications:

  • M112.970: 2001–2004 ML 350 (W163)
  • M112.972: 2002–2005 S 350 (W220)
  • M112.975: 2002–2005 S 350 4MATIC (W220)
  • M112.973: 2001–2006 SL 350 (R230)
  • 2004–2008 V 350

See also

  • List of Mercedes-Benz engines

References