I have purchased a 2007 charger r/t recently and though I am not looking to do any serious motor work at this time I have decided that I want to free it up a little bit. I have already purchased and installed the mopar cai to give it a better look under the hood. Now I have been researching and reading and it seems that everyone says the first thing you should do is change the exhaust as the factory one is so restrictive on the 5.7 hemi's. I ordered the magnaflow #15628, because they are a good name and come all stainless w/ polished mufflers and 4" tips which I liked. It is designed to look good and be less restrictive, while not being real loud, but a good deep roar when in the throttle. Now I am wondering what type of headers and hi flow cats to get. I am down to mopar long tubes, kooks long tubes, or the dynomaxx supermaxx long tubes. I am just looking to free her up a little more, and maybe give her a little more of a growl. If anyone has any advice I would appreciate it.