SPE Motorsport 6.7L Powerstroke Race Exhaust ManifoldsSPE Motorsport 6. 7L Powerstroke Race Exhaust Manifolds These are a clam shell style manifold that are CNC machined and then expertly tig welded together. The manifolds are standard 1018 mild steel they are specifically designed around the 6. 7 Powerstroke engines firing order and are 2000+hp capable. Features & Benefits: 1018 Steel uncoated* All flanges are CNC billet All welding is done in jigs for a perfect fit Includes a 2" mating V band and clamp