Hope this is helpfull, I've had a 2006 expedition and a 2003 f150 with the 4.6 v8 and I've done a lot of research. First off check out a company called bbk @ bbkperformance.com. They make upgrade kits that include throttle bodies and intake, they also make pully kits, headers, and other cool stuff. Also if u want to change exhaust, id suggest going with straight pipes, because they sound cool and on my f150 give a nice boost in hp on the higher end of the rpm spectrum. hope ive helped! good luck with your expo