Quote Originally Posted by PitchBlackC3 View Post
Unless you are going with some serious boost, I doubt you want the iron heads. You can get 317s super cheap all day long. The LQ9 has 317s too. I wouldn't use them on a 5.3 though, compression too low. What are your goals with your engine?
Also you should have 799s or 243s if you have a NNBS. Those are hard heads to beat on a 5.3.