A while back, we conducted a course in Exhaust Anatomy 101 to provide a beginner’s look at aftermarket exhaust systems. Now that you’ve brushed up on the basics, we’ll show you what makes an aftermarket exhaust system such a popular upgrade and provide tips on how to choose the system that’s best for your vehicle.
So what makes aftermarket exhaust systems one of the most popular performance upgrades among hot rodders? Like aftermarket headers, performance exhaust systems are built differently than their stock counterparts to reduce power-robbing restriction, promote exhaust scavenging, and ultimately free up more horsepower.
The first difference between a stock and aftermarket exhaust is the diameter of the pipes. The diameter ranges available on aftermarket exhaust systems vary depending on the application. However, these systems typically come with larger diameter options to flow larger volumes of air. Again, the proper diameter size will depend on variables such as engine size, rpm, application—a Summit Racing sales rep can help you choose the right size for your specific vehicle.
The second major difference between stock and aftermarket exhaust systems is the pipe bends. Stock exhaust pipe is typically formed using a technique called crush bending. Although crush bending is a quick, easy technique, it also causes performance-robbing restrictions at the pipe bends. To eliminate these restrictions, aftermarket exhaust manufacturers use a process called mandrel bending. This process utilizes a flexible rod, which is inserted in the exhaust pipe. As the pipe is bent, this flexible rod prevents the pipe walls from collapsing or kinking. The result is consistent pipe diameter with no restrictive kinks in the bends.