Headers

Well, it depends, the right intake with supporting parts along with headers will net a few ponies, the problems come from misinformation, mismatched parts and the mindset of bigger is better.
What are your goals for the car?
 
I'd do the intake and x pipe, buy with stock heads and cam the oem headers are fine.

Now if you were changing out the heads and cam, go for it.

The point is rather than headers right now, 3.73s would be a better alternative