| An exhaust header is an after market automotive | | | | headers use 1-3/4-inch tubes. An important |
| part designed to improve vehicle performance. | | | | consideration when choosing headers is quality of |
| The small gain in performance facilitated by an | | | | materials. Header tubing vary in thickness, but a |
| exhaust header is important to high performance | | | | good quality header should use between 18-gauge |
| drivers who often make other modifications to | | | | and 14-gauge tubing. The metal used in the |
| their vehicles in order to increase speed. These | | | | header is also important. Some headers are |
| modifications include the installation of larger intake | | | | mild-steel, which will rust and corrode over time. |
| vents for the engine. An exhaust header modifies | | | | Headers can be coated, either with a ceramic |
| the exhaust system to prevent back pressure, | | | | coating or a high-temperature paint. Using 100% |
| meaning that the cylinders do not have to work | | | | stainless steel construction eliminates the need for |
| as hard to push exhaust out as they do in a | | | | coatings, but it is usually out many buyer's |
| traditional system. There are different types of | | | | budgets. When headers are shipped, they |
| exhaust headers depending on the needs of the | | | | sometimes come painted. Be aware that this |
| drivers, with some tuned for low performance | | | | coating is only for rust prevention during shipping, |
| and others aimed at high performance on the | | | | and the paint will not hold up to the heat once the |
| open road. | | | | header is installed. When headers are added along |
| In a conventional exhaust system, after the | | | | with a cat-back exhaust and high-flow catalytic |
| cylinders combust, they push the exhaust out into | | | | converter, you can usually gain 20-30 horsepower |
| the exhaust manifold, which routes the exhaust | | | | over stock. |
| out of the vehicle through the exhaust pipe. | | | | In some cases, an exhaust header can be tuned |
| However, the exhaust manifold can create a back | | | | to pull at the exhaust valve of the next cylinder |
| pressure which pushes against the cylinder, | | | | and suck the exhaust out, meaning even less |
| meaning that it has to exert more energy to | | | | work for the cylinder. Drivers who desire more |
| push the exhaust out and prepare for the next | | | | power for around town driving and better |
| firing. As a result, some efficiency can be lost. | | | | acceleration under a heavy load usually opt for a |
| An exhaust header works differently, essentially | | | | low performance exhaust header, while drivers |
| creating a miniature exhaust pipe for each cylinder | | | | who are looking for speed on the open road |
| and routing the exhaust to a centralized collector | | | | prefer high performance headers. |
| which is much larger. The pipes of an exhaust | | | | A variety of manufacturers make exhaust |
| header are bent to fit under the hood and cut to | | | | headers for a dizzying assortment of vehicles, |
| the same length so that the exhaust gases will | | | | and it is important to install the exhaust header |
| arrive sequentially in the collector as each cylinder | | | | designed for your car. Because exhaust leaks can |
| fires. This eliminates the back pressure problem | | | | be dangerous, the exhaust header should be |
| and allows the cylinders to operate more | | | | installed with care, or professionally if there is any |
| effectively. | | | | uncertainty. An improperly installed header could |
| Aftermarket headers can be bolted in place of | | | | lead to an exhaust leak which vents into the cabin |
| the stock cast-iron headers. Small block headers | | | | of the vehicle, causing symptoms of carbon |
| usually use 1-5/8-inch primary tubes and big-block | | | | monoxide poisoning in the driver and passengers. |