The 4.6 2v's can make power, but nothing outrageous without some money. The new-edge 4.6's have PI intake which is a major restriction on the older 4.6's. There are swaps out there to convert the old 4.6's to PI and I believe it costs around $1-2K
96-98 4.6s have diffrent heads, cams and intake then the 99-04 4.6s which is why the older ones made 215-225hp and the newer ones made 260hp. i'v swapped the newer cams in and put the new intake on and it makes a huge diffrence in power.