How Does A Performance Exhaust Increase Horsepower?
By the basic principle of fluids (gases are a fluid) traveling in pipes. Generally, gases go faster in tubes with smaller diameters and slower in pipes with larger diameters. However, fluids still move more freely in pipes with a larger diameter.
For example, when the engine is at low RPM, pipes with a small diameter can help it breathe better. In this case, the engine produces less gas, and the higher speed in the pipes is beneficial. That said, small tubes can limit the flow at higher RPMs and choke the engine. The result will be a significant loss of power. You can even buy a holden commodore VE & VF exhaust system for sale online.
When car manufacturers design exhausts, they tend to choose a diameter that is in the middle. This way, the engine works optimally at lower and higher RPMs. Performance exhausts tend to have larger pipes more often than not. This means that your motor might lose a bit of the low-end potency, but it makes gains at higher RPMs.
Some high-end exhaust manufacturers take things to a higher level with designs that bring improvements on both fronts. Their designs include narrow and wide tubes for a combination of low RPM torque and top RPM power. These systems also have mufflers and resonators that allow for better airflow.
We will, however, not dive that deep into engineering a sound exhaust system. These companies have experienced engineers and a lot of R&D that results in products that can improve the power of your engine. That’s why high-end performance exhausts tend to cost much more than low-end ones.