power control module is a good way to add hp. it reprograms your computer and sends the correct map to the computer for timing and ignition. the cost is anywhere from $400 to $550. hypertech.com have them with links to other companies as well. the pcm first loads the stock settings and saves them,then ask a series of questions such as tire height,shift point etc. the reason it saves the stock settings is if you want to return to stock you can do so in a matter of a few minutes. i've read claims of 50+hp gains depending on the engine size. contrary to claims of voiding warrantees is false,however if your car dealer found out they may void any extra warrantees off offered by them. HAPPY MOTORING...