After market exhaust will help out on fuel flow and fuel getting burnt. Theirs many different brands of exhaust in the world. And another thing that goes with the exhaust system is the headers or manifold. Some brands of headers that I know of are hooker headers which are a exhalant brand that is on my truck now. They make headers for every car made and if not they will make it. My Honda has a turbo and a custom made header on it to do the turbo and exhaust system it comes out in front of the back wheel. We customized frame and other modifications’ on that car to make the $1000.00 exhaust system that the owner bought. The muffler that ends the system sits on the ground when he lets the air bags down. It’s crazy piercing the systems for any vehicle to upgrade it. Example my Mazda it cost $600.00 for the exhaust system for it and it’s a level one and the header coast almost $500.00 upgrading gets pricey and hard. You run into problems and slight customizations you have to make to fit your part on. Headers look cool and might sound a little better but I recommend that you leave it stock. I have run into so many problems customizing parts to make it fit on the car. A big problem that scares me is ill have to cut and plate the frame and make a spots for the bends in the system to be well placed.