I really need help!!! I have a 2000 Suburban with a LM7 5.3 that I put an Elgin E1840P ( Stage 2 ) cam with the recommended LS7 lifters and 7.400" pushrods. I'm getting what seems like the valves are staying open around 4K, (popping) I'm using a Diablosport tuner and I have 40 series Flowmaster with a cold air intake. Sounds great but RUNS really bad!!! And the rocker ticking is horrible!! Any suggestions would be appreciated!