Exhaust Header for 1973-1985 Small Block Chevy GMC Truck Blazer Suburban 1-5/8 2wd/4wd 250/292/307/350/454 4.1L 4.8L 5.0L 5.7L 7.4L 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: 1973-1985 Chevy Truck Blazer Suburban Pickup Small Block 2wd/4wd 250/292/307/350/454 4.1L 4.8L 5.0L 5.7L 7.4L 1973-1985 Chevy C10 250 292 307 350 454 Small Block 2wd/4wd 250/292/307/350/454 4.1L 4.8L 5.0L 5.7L 7.4L Specifications: Brand Name: SPELABCertificate: ISO9001:2000Application: Automobile Exhaust HeaderMaterial: Stainless SteelSurface: Mirror PolishModel:EH28200 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.