Obviously an exhaust system by itself is nothing to write home about. Of course, if you had a brand new shiny exhaust system by itself , sitting on your coffee table... well, that might be something to write home about. But insofar as it is a part of your car, the exhaust system is useful because there is an engine expelling noxious fumes and smoke as a byproduct of the combustion of fuel . Many of us did not have auto shop classes in high school , so it is probably not a bad idea to start with an informal overview of the fuel-consumption process.
The intake valves attached to the top of a given cylinder (most car engines have at least four of these) suck a mixture of fuel (from the gas tank) and oxygen into that cylinder's chamber , where a spark plug (or glow stick ) ignites the mixture, causing a controlled explosion. The energy of this explosion (combustion) is then transferred to the cylinder's piston, which is moved up and down by a crank-shaft, which in turn generates power for the transmission and finally sets your wheels in motion. This is an abbreviated version of course.
In the United States, ell exhaust systems include a catalytic converter and a muffler (in the UK, this is called a “silencer”). The job of the catalytic converter is to reduce the toxicity of you engine's exhaust. These were first widely introduced on series-production automobiles in the US market for the 1975 model year in order to comply with tightening EPA regulations on auto exhaust. If you have ever traveled to a region of the world where catalytic converters are not required for automobiles, you already know that they are a tremendous help in promoting better ambient air quality.
The job of the muffler , as you might have guessed, is to dampen the loud noises caused by combustion. Technically speaking , these sounds are in fact exhaust , for the same reason that the smoke that comes out of the tail pipe is exhaust. Both are manifestations of energy lost during the combustion process. Most stock mufflers are designed to eliminate as much engine noise as possible. However, many who invest in their vehicle's performance opt for less dampening, choosing instead to let their engines--- optimized by a performance exhaust system--- let out a healthy growl as they drive by.
Now, in an ideal world, all of the fuel you pay for at the pump would be turned into energy to power your car. However, thanks to the second law of thermodynamics, this is not the case. Much of the energy of combustion is lost in the form of exhaust. (This was true even in the days of horse-drawn carriages. For these, however, the exhaust system was a little more unpredictable and... umm... messy. ) The efficient and thorough extrication of exhaust from your car's cylinders can improve both its performance and fuel economy and it is for this reason that a Magnaflow performance exhaust system could be a wise investment for you.
It doesn't take too much reflection to realize that the cylinders we just mentioned, and the other parts involved in the process of combustion, can do a much better job of turning fuel into power for your car if exhaust can be removed more quickly from the cylinder chambers to make room for a purer mixture of fuel and oxygen. So how can one improve the typical exhaust system to achieve these benefits? Read more...