I’ve got a 2019 5.7 chally Shaker straight piped. Looking into kooks long tubes headers for a performance gain. And I saw the headers come with a (mid pipe) what is that pipe for (performance) Now I need a legit Cam for the 5.7, what else would I need to buy so that I won’t have any problems with the engine. Lifters ? Etc. also a legit throttle body please.