Exhaust headers route exhaust gases from the engine.
Place a new gasket onto the mounting surface. Fasten the gasket to the engine with small pieces of tape on either end so it doesn't move while you install the headers.5. Slide the new headers into position on the motor.
1. Open the hood. Remove any components that are in the way of the headers. This will vary greatly depending on the make and model of car. Usually, the fuel system or part of it must be removed to access the header bolts; on older cars, this may mean the carburetors and the intake manifold, while on newer cars it will be parts of the fuel injection system, the manifold and other components. Cars with a V-shape to the cylinders (V8, V6, etc.) will have a pair of headers, while cars with an inline engine (I-4, I-6, etc.) will have one header on one side of the engine.
2. Disconnect the header or headers where they are fastened to the downpipe or to the exhaust system. Again, this will vary depending on the type of car you are working on. In many cases there are three bolts holding the header to the downpipe, or the header may slide into the rest of the exhaust and held on with a muffler clamp.
3. Remove the bolts that hold the header to the engine, using the appropriate sockets and extensions and/or open-ended wrenches to reach the bolts. (The number of bolts will vary depending on the make and model.) Slide the headers out of the engine bay.
4. Clean the surface where the header mounts with degreaser and wire brush so that the surface is clean and free of oil and residue as well as any old gasket material.Exhaust headers serve to route spent exhaust gases from a automobile's engine to the exhaust system. Headers require replacement if they become cracked or worn and develop subsequent exhaust leaks. You can also replace a car's headers to get more performance from the vehicle via a more efficient header design.
Loosely thread in a bolt (or whatever fastener is used for the headers) on either end of the headers to hold them in place. Install all the bolts, then progressively tighten them with a torque wrench to the manufacturer's recommended settings.
6. Connect the downpipe or the exhaust system to the back of the headers. Replace the engine cross-member if it was removed. Reinstall the manifold and fuel system components that were removed. Start the motor and check for vacuum leaks in the headers. Re-tighten the bolts that hold the header on after the vehicle is driven to operating temperature, and periodically check that they are still tight.