I am just wonder what is the best performance chip or tuner available for the 4.6? Would a Chip or Tuner be better? What one? What kind of gains should one expect from these devices? Thx in Adv.

 

Best depends on what you are looking for. Most power? Custom programming? Ability to read codes? Ability to determine your own shift points?

 

HP and Torque primarily but improved MPG would be nice too.

 

MPG? Forget about it. Current tuners/chips are designed for power, not mileage. Any mileage gained will be offset by the fact that you must run premium fuel. For power go with a Diablo Sport chip. For the most flexibility go with a Superchips Microtuner. If its a 99 or newer, Diablo has a tuner they are working on, but its too soon to publish specs.