I've got an 06 King Ranch with a 5.4L. I'm running a K&N CAI, Magnaflow catback system, Hellwig sway bars, Bilstien 5100s all around, an Edge Evolution in the works. I don't want to add a blower at this point. Looking for ideas on other performance mods that I haven't already done or considered. Is an electric fan unit a worthwhile investment, for instance? I considered headers but rejected that as a lower gain for the $$. Thanks in advance,

 

yes efans give gain along with programming.

 

From the sounds of it, a fan kit and headers are just about the end of 'bolt on' performance mods for you. That is, unless you want to upgrade some of the bolt ons that you already have on it.

Of course, there's always a blower...