Automotive Exhaust Systems

Believe it or not, gasoline engines are relatively simple machines. Looking at engine schematics would probably convince you otherwise, but the reality is that gas engines operate by combining a few simple processes that actually aren't that hard to understand: combustion, mechanical drive and exhaust. So why is it so hard to fix your car by yourself?

The problem with modern gas engines is that they have become increasingly specialized and fine-tuned. If you're only interested in understanding how a combustion engine works, it's best to ignore all the futuristic trappings you'll find on late-model cars and focus on the basic mechanism of the engine. If you want to understand why today's cars are faster than anything before them, however, you have to dig a little deeper. Today's engines aren't all that different from the first gas engines--they're just built with a much higher degree of precision.

How Does Exhaust Make Engines Faster?

Increasing the power output of a combustion engine is all about maximizing the efficiency of the combustion itself. Since the power of the engine is literally derived from the explosion created by burning fuel, the best engines will utilize the maximum possible amount of the energy released by this explosion. High-performance engines are nothing more than an extremely precise machine intended to translate combustion into motion with virtually no energy loss.

One of the most overlooked aspects of the combustion engine (at least from a layman's perspective) is the exhaust system. Many people think that a car's exhaust system does nothing more than channel out the waste product of the combustion reaction. While this is true to an extent, the way in which the exhaust exits the engine is crucial to its power output.

Put simply, an engine needs to remove exhaust as efficiently as possible in order to run efficiently. Without a good exhaust system, an engine will literally become bogged down by its own waste product. Excess gases and compounds can quickly choke up your engine, drastically reducing performance.

The Three Functions of Exhaust Systems

Modern exhaust systems have three major functions that allow your car to run more cleanly and efficiently. The first function, as mentioned above, is to quickly remove exhaust from the engine so it can continue to burn gas without interruption. The best exhaust systems create a sort of streamlined tunnel that allows (and helps) the exhaust to escape quickly.

The second major function of an exhaust system is to reduce sound. If you've ever heard a car or motorcycle with a faulty muffler, what you're hearing isn't a mistake--it's the actual sound that the engine would make without any sound dampening. Mufflers do an incredible job of reducing the explosive sound of your engine to a dull hum.

The third function of an exhaust system is to remove polluting emissions. This is a function that was adopted only in the last few decades as scientist and government agencies discovered how much pollution automotive emissions were adding to the environment. With the help of filters in your exhaust system's catalytic converter, a large percentage of the engine's pollutants can be stopped before they enter the atmosphere.