I did some reading up on these little things. It works for any FI engine. I did a similar mod to my Mustang, just to see what it did, only mine is smarter than this thing.
What he is selling is a 15 cent resistor (probly about 40 ohm) that you wire in place of your IAT (Intake Air Temperature) sensor.
It makes the engine computer think that it's getting colder air than it usually is. Colder air is denser air, which means more O2 per cubic foot. It also means that the engine is cooler, and less likely to have premature detonation. When the computer sees this, it adds more fuel, to keep the gas/o2 ratio the same. It also advances your timeing, because it is not as likely to detonate.
If you put this resistor in on a really hot day, and keep using 87 octaine fuel, then you are really risking detonation, and blowing a headgasket.
In my Mustang, i did something a bit different. I got a Potentiometer (POT, Variable Resistor, big red knob) and put it in my dash. I then ran wires from it, and wired it in SERIES with the IAT Sensor. Now, when I turn the knob all the way to my left, it is not adding any resistance to the circuit. The engine gets a normal reading from my IAT sensor, and everything is normal. But if I need a little extra power (and I do mean very little) then I can turn the knob up a bit. It takes the resistance of the sensor, and adds a bit more resistance, making the computer think that it is colder out than it really is. This can be a dangerous thing, but all I have to do is make sure to not turn up the knob on a really hot day, and I also make sure to use middle or high octaine fuel.
High octaine fuel helps prevent detonation. That's why it is needed on high compression engines, or engines with agressive timeing.
That's my .02, let me know if you have any questions.