These Hooker BlackHeart cast iron exhaust manifolds for the popular GM LT motor has a 2.5-inch outlet and are designed to hug close to the engine block so they fit into a wide variety of replacement and engine-swap applications. Their contoured design guides the exhaust directly toward the exit port for improved flow and minimal turbulence. Cast iron construction means they will provide years of leak-free performance with less under hood noise than traditional headers and their shorty design means you can route exhaust tubing close to your frame/floor pan for maximum ground clearance. OE quality MLS flange gaskets and hardware are included to ensure excellent fitment and a leak-free installation and are available in plain as cast finish for reduced engine compartment temperatures, improved corrosion resistance and excellent styling.