Bag'O'nails
 

I recently done an oil change but my importer (based in UK) supplied me with a Fram filter with no drain back valve so engine sounded like a bag of nails
Took advice from this site and replaced with a genuine Motorcraft filter so all start up wrattles calmed down
BUT
I have a horrible taps farts and bangs coming from under my bonnet (hood) I suspect it is my tappets or cam or something in that area?
I read about cam phasers on this forum that cause rattle problems due to wrong oil choice or filter
If it is my phasers(??) what the hell are cam phasers? i know they are there to advanc/retard but where are they exactly?
Anyone know how much the parts cost
Need as much help as possible as my local Ford dealer quakes when I turn up as all they can tell you is what their little computer tells them and as they only sell Euro tin boxes thats piles up into a mound of US zero:confused:
If I go ahead with replacing parts anyone out there done these jobs themselves who can inform me if I need any unique tools etc ie 700" torx bits and a glass hammer!
you can probably tell I don't know much!
2005 5.4 Triton engine by the way