[ob_1jr]

a cold air intake will help a little, but to really make it scream, you need to either straight pipe the truck or put a bigger exhaust on it.

 

[ob_1jr]

Duramax does not have that silencer ring. I wish it was that easy on our trucks to get more whistle. Mine whistles pretty good with the AFE stage II and 4" exhaust....Although, mine is an LB7. I did hear a LBZ that was straight piped (pretty sure anyway) and it sounded awesome! I only heard it in Walmart's parking lot.