Alright guys I need some major help, I have a 04 gmc Sierra 4.8l with cai,true dual,high flow cats,new injectors and rails,new plugs,wires,knock sensors,mass air flow sensor,crankshaft sensor,o2 sensors. And sometimes when I really put my foot in the pedal it takes a long time for it to pick up acceleration, it runs and cranks great but it doesn't give me that "jump" when you normally put your pedal to the metal. Do I need a tune or what? Please give me feedback.