In our September 2012 small CUV comparison test, in which the Ford Escape edged the Mazda CX-5 for top honors, the overwhelming consensus among the judges was that had the Mazda had more oomph, it would have won. As Jonny Lieberman so eloquently concluded, "Engine notwithstanding, we liked almost everything about the CX-5. If Mazda could add a little extra power, well, winner, winner, Mazda chicken dinner." With a naturally aspirated 2.0-liter Skyactiv I-4 producing 155 horsepower and 150 lb-ft of torque, the FWD CX-5 needed 9.4 seconds to saunter from 0 to 60 mph and 17.1 seconds at 79.9 mph to nudge the quarter mile. That's 0.5 and 0.4 second slower, respectively, than the times for the 173-hp, 184-lb-ft Escape. Zoom-zoom? Not so much.

Just one model year after its introduction, though, Mazda is adding an old-school enhancer -- displacement -- aimed at giving the sporty CUV the muscle to match its athletic chassis. About the size of an average Coke bottle, the half-liter of extra engine volume gives the new 2.5-liter Skyactiv I-4 the much-needed energy to make another run at the Escape. Output for the 2.5, which is shared with the 2014 Mazda6, is rated at 184 hp at 5700 rpm and 185 lb-ft at 3250, with both power and torque peaks realized earlier in the power band than in the 2.0. Similar to its smaller sibling, the 2.5 boasts direct injection and a 13.0:1 compression ratio, and runs on 87 octane. But that's about where the similarities end. Both bore and stroke are unique to each engine, and Mazda notes that only a handful of components are shared between the two.

While the base $21,990 Sport comes exclusively with the old 2.0, the midgrade $25,410 Touring and top-tier $28,415 Grand Touring benefit from the 2.5. The Touring's price is up $720 and the Grand Touring's $575, but those are small premiums for the 29 extra horses underhood, because those steeds pay big dividends, say, when entering a highway or passing on a two-lane. Whereas before those maneuvers required serious forethought and the tiny 2.0 screamed like a tired baby, the 2.5 just asks for a heavy right foot, while reducing driver anxiety and softening engine wailing. Further, the 2.5's additional 35 lb-ft of twist pulls the CX-5 off the line with a sense of purpose, something the 2.0, whose torque could best be described as "aspirational," could never tout.

Not only does the all-new 2.5-liter Skyactiv make the CX-5 feel more sprightly in all regards, it also ups the vehicle's overall refinement, something Mazda's bestselling CUV will need if it's going to dethrone the Escape and outduel such 2.5-liter newcomers as the Subaru Forester and Toyota RAV4.