While many cars and trucks of the Eighties and Nineties dispelled the notion that American performance died off with the original muscle cars, it took an entirely new engine—one more powerful and less expensive to produce than its predecessor—to reignite the horsepower wars and usher in a new golden age. The Hemi V-8 has since become a standard-bearer for Chrysler, Dodge, Ram, and Jeep vehicles, and its basic engine architecture has spawned more than a dozen configurations, some of them difficult to discern from others. For that reason, we’ve put together this spotters guide to the third-gen Hemi family of engines.
What sets the Hemi apart
Teased in the 2000 Chrysler 300 Hemi C and the 2001 Dodge Super8 Hemi, the new 5.7-liter Hemi (Chrysler stylizes it as HEMI, but for expediency’s sake, we will not) debuted in the 2003 Dodge Ram pickups, featuring a deep-skirt cross-bolted iron block, aluminum heads, overhead valves, 4.46-inch bore spacing, the same bellhousing bolt pattern as the Chrysler LA-series V-8s, coil-on-plug ignition, composite intake manifolds, multipoint fuel injection, and that controversial head design.
Like the second-generation 426 Hemi, the 5.7L Hemi heads featured opposed valves for a true crossflow design, twin spark plugs, and rocker shafts. The third-generation Hemi did not, however, feature a full hemispherical combustion chamber. Instead, Chrysler’s engineers decided to flatten either side of the combustion chamber to improve combustion efficiency and emissions.
Some might argue that doesn’t make the engines true Hemis, but then again, the Hemi V-8s of yore were massive, heavy engines that cost a lot to machine and that wouldn’t meet modern-day fuel-efficiency or emissions requirements.