All calibers with a CVT have the CVT2. I remember back when the Caliber was introduced they were advertising it like that.Your problem is the 2007 models have cvt1. Poor mapping and performance and reliability issues. In 2008 and beyond they updated to cvt2. This new cvt2 is programmed much better and you can't get it in the 07. I drive an 08 rt with the 2.4. I consistently get 19.9mpg doing city pizza delivery. The drop in k&n filter improved my mpg by 1to2 mpg and produces a noticeable improvement to acceleration. (less lag). I also use premium fuel. I couldn't be happier with my dodge's performance. *heads up* the steering rack/main gear is one unit and is built to last just 70000miles. Mine made it to 77000 and then I lost all power steering. Cost $700 to fix.
i actually got worse mileage in my caliber with premiumthere is absolutely no reason to use premium fuel in your car. You wont get ANY performance benefit, and wont get any gas mileage increase. Your throwing your money away, and with the way gas prices are now, the difference between premium and regular is sizeable.