The difference between some current American V8s and the HEMI comes down to power delivery. The engine revs freely, launching the Magnum RT to 100 km/h in 6.3 seconds, or so Dodge's conservative figure states, but my gut calculation number is much closer to 6 even.

Although the HEMI is know for sheer power, the new version is also up to 20 percent more fuel efficient. (Photo: Trevor Hofmann, Canadian Auto Press)

But while ruddy fast, Dodge hasn't forgotten that environmental concerns are paramount to today's consumers. For what might be the ultimate "having your cake and eating it too" analogy, the HEMI features Chrysler Group's Multi-Displacement System (MDS), the first cylinder deactivation system to be sold in North America on large-volume vehicles. MDS is expected to increase fuel economy by up to 20 percent while still delivering all the power and even more torque than the new-age HEMI V8 is becoming legendary for in truck and SUV applications.

Chrysler Group's Multi-Displacement System (MDS) will be the first cylinder-deactivation system to be sold in North America on large-volume vehicles. (Photo: Trevor Hofmann, Canadian Auto Press)

New developments such as high-speed electronic controls, sophisticated algorithms controlling the systems and the integration of electronic throttle control have made the technology possible. The result is a seamless deactivation and activation process, needing only 40 milliseconds (0.040 seconds) to transition from eight-cylinders to four or vice versa. After repeated attempts to transition the engine from light to heavy loads (light on the throttle to pedal to the metal) I couldn't tell when it was in 4-cylinder mode or when it switched to eight.