I have a 2004 Silverado 4.3l V6 with magnaflow exhaust, k&n Intake system. I dont get very good mpg around 17 for both highway and city it seems no matter how i dirve. I am lookin to improve MPG, and up the horses a little bit. I am not looking to turn my v6 to a beast cuz i know that just wont happen. I am wondering does anyone have experience with the E-con or know anyone who does? I would like to see others opinions on this programmer before i drop 330 on it. Any advice would be appreciated. Thanks.