Now that we have changed our intake to allow our engines to breath easier we need to change our Exhaust so that we can get rid of exhaust gasses a little better. There are several ways to accomplish this task, the most common is too purchase a cat-back kit from someone like flowmaster or magnaflow. I personally prefer flowmaster because they have shown the biggest increase in MPG while keeping the noise increase minimal. A flowmaster kit can be installed in your driveway with some ramps, handtools, and a lot of patience or you can have it installed professionally for less than one hundred dollars in most cases. Another option is to have an exhaust shop custom fab an exhaust for you. While it may sound expensive you can usually have this done cheaper than you can buy a cat-back kit and have it installed.