SPELAB Exhaust Header for 2009,2010,2011,2012,2013,2014,2015,2016,2017,2018 Hemi 5.7L Dodge Ram 1500 Manifold Replacing or upgrading your exhaust header is necessary for both engine performance and sound. Whether on or off the track, exhaust headers provide more horsepower and improved exhaust sound. SPELAB offers many products to help you create your own custom engine headers. It's really easy and convenient to use: direct bolt-on, no modification needed. Fitment: Short Header&Manifold : 2009-2017 5.7L (345 cu. in.) Hemi V8 Long Header&Manifold : 2009-2018 5.7L (345 cu. in.) Hemi V8 Not compatible with 4WD. Shorty Header Specifications: Brand Name: SPELABSKU: SPES08294Header Type: Shorty/Short TubeCollector Diameter: 2-1/2 in. (64mm)Head Flange Thickness: 3/8 in. (9.5mm) Primaries Diameter: 1-5/8 in. (42mm) Pipe Thickness: 16-gauge (1.5mm) Mounting Hardware Included: Yes Material: 304 Stainless Steel Long Header Specifications: Brand Name: SPELABSKU: SPES08237 Outlet Size: 3.00"Primary Tube Size: 1.75"Head Flange Thickness: 7/16"Outlet Flange Thickness: 3/8"CNC machine flanges with TIG and MIG welded construction 3 Stage polish finish. Mounting Hardware Included: Yes Material: 304 Stainless Steel Exhaust Header VS Manifold, which is the better choice? The structural differences between exhaust headers and manifolds are the material and size. From the material, exhaust headers are made of lighter, thinner steel, while exhaust manifolds are made of thick iron. Exhaust headers are also longer than exhaust manifolds. When in use, exhaust manifolds create back pressure, which lowers performance. Because each cylinder of the engine is given its own tube, however, headers eliminate this problem; thus, allowing the gases to exit without the creation of back pressure. Therefore, exhaust headers are a BETTER choice than an exhaust manifold.