http://www.motortrend.com/roadtests/...ing_specs.html
"Most impressive are the performance increases of the six-speed Grand Touring-trim Mazda3 we had in for testing. That newfound power helps to cut nearly half a second off of the 0-to-60 time of the outgoing Mazda3 with the same trim package, at 7.6 sec (versus 8.3). The trend continues with the 3 accelerating through the quarter mile at 15.8 sec @ 87.8 mph, more than 1 sec quicker and 2 mph faster than the previous-gen car. The new 2010 Mazda3 now accelerates faster than the 2009 Corolla XRS, which was the quickest vehicle in four-door compact car comparison mentioned above."
Pour ce qui est de la consommation tu as peut-être raison par contre, dans l'article il dise que la consommation est la même que le 2.3, mais c'est possible que sa soit un peu plus.