For my 03 Ex, 4.6l... which mod would be best for power/efficiency/performance? Not really concerned about "sound" from the exhaust. I just want to squeeze a little more hp out. I have an AF1 intake and the TP Xcal tunes (93 performance). Otherwise, it is stock.

If you could only get one (for now), which would it be?

 

For me, E-fans as I already have intake, exhaust, programmer.
For you, exhaust to round out the intake and TP tunes.

 

I think you would see the best gain with the efans, but the exhaust would round out what you already have done.

 

I was looking at the magnaflow site at their dyno curves. for a 5.4, they only show a few hp increase with their exhaust...now I assume that is for stock everything else, so its definately not an apples to apples comparrison. I would like to have some idea of what it would yield with the intake and the tunes. anybody venture an educated guess?

I have *heard* that the efans will yield around 17 hp by getting rid of the mech fan. Not sure about that as I haven't actually seen any data, just word of mouth on this site.

 

I know, Im thinking hard of getting e-fans for both of my motors, 2001 5.4L lariat 4x4, 1997 4.6L 4x4 expedition, seems to be the best upgrade no matter who ya talk to....