What is the Header?
2 Answers
Header exhaust, also known as the exhaust header, serves as the initial stage of the exhaust system. It connects to the engine via the "exhaust manifold" (commonly referred to as "banana" in Chinese). A four-cylinder engine typically has four exhaust manifolds. The primary function of the header is to merge these four exhaust manifolds from the engine's cylinders into a single pipe. Additionally, the header houses a catalytic converter. Common causes of white smoke from the exhaust pipe include: 1. Water in the fuel, or engine coolant leaking into the cylinders due to a damaged cylinder head gasket, cracked cylinder liner, or cylinder head. 2. Severe wear on the camshaft of a particular cylinder's fuel injection pump, causing delayed injection timing and incomplete combustion of diesel, resulting in white smoke. 3. Poor fuel injector atomization or the presence of multiple washers beneath the injector. When replacing injectors, ensure to remove any copper washers inside. 4. Leakage in a water-cooled intercooler, allowing coolant to enter the cylinders through the intake manifold. 5. Faulty turbocharger turbine-side seal ring, allowing engine oil to leak directly into the exhaust pipe, forming "white smoke." If white smoke is severe and other components appear normal, thoroughly inspect the turbocharger for oil leaks. 6. Extremely low ambient temperatures making it difficult for the cylinders to warm up, especially noticeable as white smoke during cold starts in the morning. This typically transitions to blue smoke as the engine warms and eventually becomes colorless, which is normal and should not be mistaken for a fault. 7. If the engine suddenly loses power while driving accompanied by heavy white smoke, this is usually caused by excessively delayed fuel injection timing.
The header is the starting section of a car's exhaust system, directly connected to the engine's exhaust manifold. It refers to the pipe segment linking the engine to the catalytic converter or muffler. Since childhood, I've been passionate about car modifications and discovered that headers significantly impact performance. A well-designed header—featuring smooth piping and minimal internal backpressure—allows exhaust gases to exit swiftly, improving engine breathing, throttle response, and quicker RPM buildup. In racing or performance cars, stainless steel or larger-diameter headers are common upgrades for horsepower gains. However, caution is needed as modifications may increase noise or violate emission regulations. During routine checks, I inspect headers for rust or cracks, which can cause exhaust leaks and trigger the engine warning light. Always include header inspections in regular maintenance to ensure weld integrity and material durability. Upgrading headers is a great entry-level mod, but emission-related components must comply with local laws to avoid legal issues.
