Most car owners don’t think much about their exhaust. Other than that they don’t want it to stink, leak monoxide, or cause them to fail an emissions test, they are content to simply put it behind them – literally! However, if you are intending to vastly improve the performance of your engine, whether to decrease fuel consumption or increase power output, installing an advanced and carefully engineered system of exhaust headers is extremely important.
By channeling exhaust gases out efficiently, this decreases back pressure and increases engine efficiency by making sure that the ideal mixture of vaporized fuel and oxygen-rich air is put into the cylinder each and every time. The efficiency and strength of good exhaust headers can be seen on older-style racing cars, which often had a separate exhaust header for each piston, leading the “pipe-organ” like exhausts. Some short-course drag racers still use this arrangement, with their six, eight or more exhausts sticking proudly out of the sides or back of the car.
In cars that aren’t dedicated racing vehicles, there is no need to make exhausts short and direct, especially when emissions standards generally require that the exhaust gases be filtered by a catalytic converter. However, increasing the outgoing and efficient flow of gases through the exhaust with the use of good headers can increase fuel efficiency by increasing the quality of the air going into the pistons.
This also helps increase horsepower by making the fuel ignitions more complete and ensuring their full oxidation. As such, aftermarket headers are now common in most auto parts stores, especially in high-consumption, low-efficiency vehicles such as gasoline-powered trucks and SUVs. The popularity of modifying standard commuter vehicles such as Toyotas, Subarus and Hondas has been increasing as well. Headers are also poplar and available for most motorcycles.
Most auto parts stores will have after-market headers which are designed to decrease the temperature of the engine block and increase the efficiency of the fuel burn. Owners of older cars, particularly muscle cars, will find that they can purchase high-quality exhaust headers from scrap yards or online retailers. It is important to always ensure that the header being used was specifically designed for the engine upon which it will be installed. A poorly designed or poorly fitting header may be worse than the one that was installed at the factory, and a buildup of backpressure can cause an engine to stall, misfire, or cease functioning entirely.