I have a 02 F150 4.6l 2x4 king ranch w/stock size tires. I want some more power off the line but I dont want to kill my highway driving. I do a fair share of highway driving right now.

I heard that changing your gear ratios and give me more low end torque, but less high end power. Is this true? A few numbers have been tossed around... 4.10 and 3.37. I don't know which one I need.

Is there a kit out there for my truck for this? if not, what parts do I need?

Basically, I am clueless as to how all this works, I just want more power to peel out! :-)