This is my first time on one of these sites so bare with me please. I was wondering how to find this book you guys were talking about. The one that you can download to help you understand tuning better. I also have purchased the jet DST software. I have been able to read my truck into the software, edit it, and program back to truck. But I dont really know exactly what I am doing. As I would just like to advance timing. Try to get more fuel. And probably play with the shift points. I have more in store for this I6. At the moment I have a K&N cold air intake, and nos wet kit with drive by wire programmable activating module. 250 hp. shot for now. turbo in near future. Know anybody else doing anything with the 4.2 liter?