I just traded my 97 F-150 with a 4.6 and my new truck has the 5.4 . I pull a bass boat and it didn't seem like the 4.6 was doing the job when I drove into the high country (not too bad on flat highway drive) I was quite surprised how easy the 5.4 pulls my boat. Sorry I don't have a technical answer for you but I can tell you it's a big improvement in pulling power. I had dual exhuast and The K&N performance kit on my truck with the 4.6 and my gas milage was about 15 MPG and that's about what I'm getting with my 5.4 without any add-ons.

Dave

 

I see a lot of useless posts in here. I think a few of you suffer from Small Man's Syndrome, bigger is better............ Give me a break.