I have a 2009 LS 5.3 Gen 4 LMG engine and am looking to see what kind of power upgrades I can make to it, while staying naturally aspirated. From what I have seen, it appears Chevy has done a really good job matching parts like cams to heads and have designed really good stock manifolds, ect. What kind of upgrades are everyone doing and what kind of power increase are you seeing?