There are a lot of threads on these. Don't waste your time, money or engine life on this POS. Horsepower ain't cheap. All those resistors do is fool your PCM into thinking that the incoming air is colder than it really is. Hence, it will compensate by changing the air/fuel ratio so you actually burn MORE fuel.
If you want real "bolt on" horsepower, go with a tuner, pullies, exhaust. That'll be $800 please.