I have a 2001 F-150 5.4L 4x4, some mods like exhuast and cold air. I was looking at getting some better bigger Cams. Looking for some that arent to tuff on my stock motor(if there is any). My friend put some on his 03 V10 and it sounds great!
The cams for these engines are very, very expensive and difficult and timely to install. If you have the money and a good mechanic or know-how, Comp-Cams and Crane both put out a line of SOHC bump sticks. I wouldn't do it just for the sound though, it'll effect the driveability on-road. You'd need headers, bigger throttle body, bigger injectors, and a hotter ignition system, and a custom tune to take advantage of the cams though. It's only money! lol
There is a lot of HP to be made with a BIG(long duration, high lift) cam or in your case cams. Imagine if you had a double overhead cam "V" engine. You'd have to buy 4 camshafts to make the change your thinking of. You don't need heads or headers just because you change your cam(cams), but it sure helps. A reflash would also be a good idea if you decide to go a high performance cam setup. One thing that is also needed if you have an auto trans and I'm guessing you do(I don't think Ford currently offers a manual) is a high stall torque converter. That means the trans or block has to come out. As far as fuel injectors are concerned you don't need to change those if you just change the cams and stay N/A and keep your current injectors at or less than 80% duty cycle. If you go over 80% duty cycle (or if you go F/I) then you probably will need bigger injectors. One thing that helps mitigate drivability issues is to keep the LSA on your new cam pretty wide. Sure a narrow LSA sounds good(very lopey), but as you've already been told sound isn't the only reason to do a cam swap. The most popular truck to do a cam swap on is the Chevy Silverado. It is a single cam like the Ford truck,but it's cam in block not overhead cam like the Ford. On the Silverado the you can change the cam without removing the intake or the heads. All you do is remove the crank pulley, timing cover, rocker covers, rockers and pushrods. The block is gun drilled all the way to the back of the block. After you remove the timing set you spin the cam and put 5/16" wooden dowel rods into the block to hold the lifter up while you remove the OEM cam and install your new high performance bump stick. Thousands of Silverado owners have done their own cam changes in their driveways or had a friend or shop do it for them. The LS series engine in the Silverado has become a cult engine. So much so it has its' own website. Changing a cam on a Ford is much more expensive and complicated than on the Chevy.