I have an 08 tahoe with the 5.3. I am running a spectre cold air intake and a corsa exhaust. I also got a diablo tuner and have tweaked with it a bit. I added 3 degrees of timing and pulled 3% on the fuel. Things tacks out hard on the big end between 4000-5500 RPM, seems to be lacking in the mid range. Any suggestions on what kind of tune to run?