Upgrading a 2001 Tribute
 

I have a 2001 Mazda Tribute ES V6 4WD, and I am looking at upgrading it a bit engine wise. Some of the first things that come to mind are an aftermarket airbox, throttle body, intake, and exhaust. Would remapping the engine make much of a difference? And with an aftermarket intake, and throttlebody, would enough air be getting into the engine for bigger injectors to make a difference?

Save your money; you might be able to coax a few extra horsepower out of the engine up near redline at wide open throttle, but in the midrange, where you do over 99% of your driving, you will actually lose a bit of power.

How would I be losing power?

When you change the flow and turbulence characteristics in the intake and exhaust for higher power (which by definition means high RPM) optimization, the resonance which aids mid-range volumetric efficiency hurts mid-range torque. Most engines are a compromise between mid-range torque and high-end power; enhance one, hurt the other. Fact of life.

The above said, with trick two/three/variable intake manifold systems and/or forced induction, the trade-offs are not as extreme.

Could remapping help optimize it for more low end power?

Nope, the map has nothing to do with it; the Ford/Mazda engineers who developed your engine were very well schooled and experienced; the compromises made between high end power and mid range torque had been known for many decades by then and are still just as much a fact of life now. The truth is, if you optimize one, you mess with the other.

If you really want more power, both mid-range and high-end, you're going to have to consider forced induction. The problem with that is, for what it would cost you to breathe on your engine, you can sell your Tribute and buy something as functional but rather faster/more powerful.