2008 4.7 with very little power

[Mopar4jon]

I just purchased a 2008 dakota Laramie 4.7. as a project truck, it has 107,000 miles on it. I noticed that the low end torque is great but its got nothing on the top end. I've had 2 previous dakotas with 4.7's and they had a considerable amount of more power. I replaced the cats so far(they were beyond bad) and new sensors. I'm curious if you all had any ideas as to what the issue is?

Thanks in advance.