Aftermarket Performance

[kayne]

I was needing some advice as to whether or not I should tune my H2 engine to get better performance ie, horsepower and gas mileage, or should i get new headers, cold air intake, throttle body spacers, and exhaust, i just dont know so i need some advice.... The guys who have tuned their engines say they have had better performance but i have not really run into anyone who has added the complete aftermarket package....