How HEMI Engines Work

The Dodge HEMI Magnum
2003 Dodge Ram with 5.7-liter HEMI Magnum V-8
2003 Dodge Ram with 5.7-liter HEMI Magnum V-8
Photo courtesy DaimlerChrysler

The Dodge HEMI engine builds off the tradition of HEMI power to deliver a 345-cubic-inch (5.7 liter) V-8 engine with hemispherical heads.

The engine produces 345 horsepower, and compares very favorably with other gasoline engines in its class. For example [ref]:

  • Dodge 5.7 liter V-8 - 345 hp @ 5400 rpm
  • Ford 5.4 liter V-8 - 260 hp @ 4500 rpm
  • GMC 6.0 liter V-8 - 300 hp @ 4400 rpm
  • GMC 8.1 liter V-8 - 340 hp @ 4200 rpm
  • Dodge 8.0 liter V-10 - 305 hp @4000 rpm
  • Ford 6.8 liter V-10 - 310 hp @ 4250 rpm
5.7-liter HEMI Magnum V-8 engine from the 2003 Dodge Ram
Photo courtesy Daimler Chrysler

The HEMI Magnum engine has two valves per cylinder as well as two spark plugs per cylinder. The two spark plugs help to solve the emission problems that plagued Chrysler's earlier HEMI engines. The two plugs initiate two flame fronts and guarantee complete combustion.

For more information on HEMI engines and their heritage, check out the links below.

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