You can find the chip tuning file for your Buick Rainier 2004 - 2007 5.3 V8 304hp vehicle on our site. These files are created especially for you and handed to you. All our Tuning files are extensively tested on Dynometer. The development of the tuning file for your Buick Rainier 2004 - 2007 5.3 V8 304hp vehicle is the result of a special product by EcuPrime Engineers. In addition, we can increase the power of your vehicle from 304 HP to 321 HP, 447 Torque to 471 Torque.