I just ignore the bickering on there. AirRam (Nick) was the guy sold parts back in the day try to help get more performance out of the 4.7L V8. He had a 2002 Quad Cab with a 4.7L for a while. I put a Y Pipe on my 4.7L Dakota but, I think I also had an ASP Underdrive pulley installed as well around the same time. I think both made a difference but, the pulley made more of a difference. Just a point of reference that pulley is no longer made and hasn't been for years. I also took off my clutch fan as well and ran the electric fan on the truck at the time. Honestly, the manifolds on the 4.7L are okay but, headers are nice especially if you can upgrade the exhaust manifold bolts that love to break then cause an exhaust leak.